diff --git a/app/Http/Controllers/App/CategoryController.php b/app/Http/Controllers/App/CategoryController.php
new file mode 100644
index 0000000..db66dc7
--- /dev/null
+++ b/app/Http/Controllers/App/CategoryController.php
@@ -0,0 +1,54 @@
+<?php namespace App\Http\Controllers\App;
+
+use App\Http\Controllers\Controller;
+use App\Http\Requests\App\CategoryStoreRequest;
+use App\Http\Requests\App\CategoryUpdateRequest;
+use App\Models\Category;
+use Notsoweb\ApiResponse\Enums\ApiResponse;
+
+
+class CategoryController extends Controller
+{
+    public function index()
+    {
+        $categorias = Category::where('is_active', true)
+                ->orderBy('name')
+                ->paginate(config('app.pagination'));
+
+        return ApiResponse::OK->response([
+            'categories' => $categorias
+        ]);
+    }
+
+    public function show(Category $categoria)
+    {
+        return ApiResponse::OK->response([
+            'model' => $categoria
+        ]);
+    }
+
+    public function store(CategoryStoreRequest $request)
+    {
+         $categoria = Category::create($request->validated());
+
+        return ApiResponse::OK->response([
+            'model' => $categoria
+        ]);
+    }
+
+    public function update(CategoryUpdateRequest $request, Category $categoria)
+    {
+        $categoria->update($request->validated());
+
+        return ApiResponse::OK->response([
+            'model' => $categoria->fresh()
+        ]);
+    }
+
+    public function destroy(Category $categoria)
+    {
+        $categoria->delete();
+
+        return ApiResponse::OK->response();
+    }
+}
diff --git a/app/Http/Controllers/App/InventoryController.php b/app/Http/Controllers/App/InventoryController.php
new file mode 100644
index 0000000..872694b
--- /dev/null
+++ b/app/Http/Controllers/App/InventoryController.php
@@ -0,0 +1,61 @@
+<?php namespace App\Http\Controllers\App;
+
+use App\Models\Inventory;
+use App\Http\Controllers\Controller;
+use App\Http\Requests\App\InventoryStoreRequest;
+use App\Http\Requests\App\InventoryUpdateRequest;
+use App\Services\ProductService;
+use Notsoweb\ApiResponse\Enums\ApiResponse;
+
+
+class InventoryController extends Controller
+{
+    public function __construct(
+        protected ProductService $productService
+    ) {}
+
+    public function index()
+    {
+        $products = Inventory::with(['category', 'price'])
+                ->where('is_active', true)
+                ->orderBy('name')
+                ->paginate(config('app.pagination'));
+
+        return ApiResponse::OK->response([
+            'products' => $products
+        ]);
+    }
+
+    public function show(Inventory $inventario)
+    {
+        return ApiResponse::OK->response([
+            'model' => $inventario->load(['category', 'price'])
+        ]);
+    }
+
+    public function store(InventoryStoreRequest $request)
+    {
+        $product = $this->productService->createProduct($request->validated());
+
+        return ApiResponse::OK->response([
+            'model' => $product
+        ]);
+    }
+
+    public function update(InventoryUpdateRequest $request, Inventory $inventario)
+    {
+        $product = $this->productService->updateProduct($inventario, $request->validated());
+
+        return ApiResponse::OK->response([
+            'model' => $product
+        ]);
+    }
+
+    public function destroy(Inventory $inventario)
+    {
+        $inventario->delete();
+
+        return ApiResponse::OK->response();
+    }
+
+}
diff --git a/app/Http/Controllers/App/PriceController.php b/app/Http/Controllers/App/PriceController.php
new file mode 100644
index 0000000..7297fd0
--- /dev/null
+++ b/app/Http/Controllers/App/PriceController.php
@@ -0,0 +1,29 @@
+<?php
+
+namespace App\Http\Controllers\App;
+
+use App\Http\Controllers\Controller;
+use App\Http\Requests\App\PriceUpdateRequest;
+use App\Models\Price;
+use Notsoweb\ApiResponse\Enums\ApiResponse;
+
+class PriceController extends Controller
+{
+    public function index()
+    {
+        $prices = Price::with('inventory')->paginate();
+        return ApiResponse::OK->response(['prices' => $prices]);
+    }
+
+    public function show(Price $price)
+    {
+        return ApiResponse::OK->response(['model' => $price->load('inventory')]);
+    }
+
+    // Actualizar solo precio
+    public function update(PriceUpdateRequest $request, Price $precio)
+    {
+        $precio->update($request->validated());
+        return ApiResponse::OK->response(['model' => $precio->fresh('inventory')]);
+    }
+}
diff --git a/app/Http/Controllers/App/SaleController.php b/app/Http/Controllers/App/SaleController.php
new file mode 100644
index 0000000..ca9a955
--- /dev/null
+++ b/app/Http/Controllers/App/SaleController.php
@@ -0,0 +1,59 @@
+<?php
+
+namespace App\Http\Controllers\App;
+
+use App\Http\Controllers\Controller;
+use App\Http\Requests\App\SaleStoreRequest;
+use App\Services\SaleService;
+use App\Models\Sale;
+use Notsoweb\ApiResponse\Enums\ApiResponse;
+
+class SaleController extends Controller
+{
+    public function __construct(
+        protected SaleService $saleService
+    ) {}
+
+    public function index()
+    {
+        $sales = Sale::with(['details.inventory', 'user'])
+            ->orderBy('created_at', 'desc')
+            ->paginate(config('app.pagination'));
+
+        return ApiResponse::OK->response([
+            'sales' => $sales,
+        ]);
+    }
+
+    public function show( Sale $sale)
+    {
+        return ApiResponse::OK->response([
+            'model' => $sale->load(['details.inventory', 'user'])
+        ]);
+    }
+
+    public function store(SaleStoreRequest $request)
+    {
+        $sale = $this->saleService->createSale($request->validated());
+
+        return ApiResponse::CREATED->response([
+            'model' => $sale,
+        ]);
+    }
+
+    public function cancel(Sale $sale)
+    {
+        try {
+            $cancelledSale = $this->saleService->cancelSale($sale);
+
+            return ApiResponse::OK->response([
+                'model' => $cancelledSale,
+                'message' => 'Venta cancelada exitosamente. Stock restaurado.'
+            ]);
+        } catch (\Exception $e) {
+            return ApiResponse::BAD_REQUEST->response([
+                'message' => $e->getMessage()
+            ]);
+        }
+    }
+}
diff --git a/app/Http/Controllers/CategoryController.php b/app/Http/Controllers/CategoryController.php
deleted file mode 100644
index c778be8..0000000
--- a/app/Http/Controllers/CategoryController.php
+++ /dev/null
@@ -1,18 +0,0 @@
-<?php namespace App\Http\Controllers;
-/**
- * @copyright (c) 2025 Notsoweb Software (https://notsoweb.com) - All Rights Reserved
- */
-
-use Illuminate\Http\Request;
-
-/**
- * Descripción
- * 
- * @author Moisés Cortés C. <moises.cortes@notsoweb.com>
- * 
- * @version 1.0.0
- */
-class CategoryController extends Controller
-{
-    //
-}
diff --git a/app/Http/Controllers/InventoryController.php b/app/Http/Controllers/InventoryController.php
deleted file mode 100644
index 5650b39..0000000
--- a/app/Http/Controllers/InventoryController.php
+++ /dev/null
@@ -1,18 +0,0 @@
-<?php namespace App\Http\Controllers;
-/**
- * @copyright (c) 2025 Notsoweb Software (https://notsoweb.com) - All Rights Reserved
- */
-
-use Illuminate\Http\Request;
-
-/**
- * Descripción
- * 
- * @author Moisés Cortés C. <moises.cortes@notsoweb.com>
- * 
- * @version 1.0.0
- */
-class InventoryController extends Controller
-{
-    //
-}
diff --git a/app/Http/Controllers/PriceController.php b/app/Http/Controllers/PriceController.php
deleted file mode 100644
index 1d7413f..0000000
--- a/app/Http/Controllers/PriceController.php
+++ /dev/null
@@ -1,18 +0,0 @@
-<?php namespace App\Http\Controllers;
-/**
- * @copyright (c) 2025 Notsoweb Software (https://notsoweb.com) - All Rights Reserved
- */
-
-use Illuminate\Http\Request;
-
-/**
- * Descripción
- * 
- * @author Moisés Cortés C. <moises.cortes@notsoweb.com>
- * 
- * @version 1.0.0
- */
-class PriceController extends Controller
-{
-    //
-}
diff --git a/app/Http/Controllers/SaleController.php b/app/Http/Controllers/SaleController.php
deleted file mode 100644
index 7e99e5b..0000000
--- a/app/Http/Controllers/SaleController.php
+++ /dev/null
@@ -1,18 +0,0 @@
-<?php namespace App\Http\Controllers;
-/**
- * @copyright (c) 2025 Notsoweb Software (https://notsoweb.com) - All Rights Reserved
- */
-
-use Illuminate\Http\Request;
-
-/**
- * Descripción
- * 
- * @author Moisés Cortés C. <moises.cortes@notsoweb.com>
- * 
- * @version 1.0.0
- */
-class SaleController extends Controller
-{
-    //
-}
diff --git a/app/Http/Controllers/SaleDetailController.php b/app/Http/Controllers/SaleDetailController.php
deleted file mode 100644
index ccdb732..0000000
--- a/app/Http/Controllers/SaleDetailController.php
+++ /dev/null
@@ -1,18 +0,0 @@
-<?php namespace App\Http\Controllers;
-/**
- * @copyright (c) 2025 Notsoweb Software (https://notsoweb.com) - All Rights Reserved
- */
-
-use Illuminate\Http\Request;
-
-/**
- * Descripción
- * 
- * @author Moisés Cortés C. <moises.cortes@notsoweb.com>
- * 
- * @version 1.0.0
- */
-class SaleDetailController extends Controller
-{
-    //
-}
diff --git a/app/Http/Requests/App/CategoryStoreRequest.php b/app/Http/Requests/App/CategoryStoreRequest.php
new file mode 100644
index 0000000..3e6cf5f
--- /dev/null
+++ b/app/Http/Requests/App/CategoryStoreRequest.php
@@ -0,0 +1,37 @@
+<?php namespace App\Http\Requests\App;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class CategoryStoreRequest extends FormRequest
+{
+    /**
+     * Determine if the user is authorized to make this request.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * Get the validation rules that apply to the request.
+     *
+     */
+    public function rules(): array
+    {
+        return [
+            'name' => ['required', 'string', 'max:100'],
+            'description' => ['nullable', 'string', 'max:225'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'name.required' => 'El nombre es obligatorio.',
+            'name.string' => 'El nombre debe ser una cadena de texto.',
+            'name.max' => 'El nombre no debe exceder los 100 caracteres.',
+            'description.string' => 'La descripción debe ser una cadena de texto.',
+            'description.max' => 'La descripción no debe exceder los 225 caracteres.',
+        ];
+    }
+}
diff --git a/app/Http/Requests/App/CategoryUpdateRequest.php b/app/Http/Requests/App/CategoryUpdateRequest.php
new file mode 100644
index 0000000..fca682d
--- /dev/null
+++ b/app/Http/Requests/App/CategoryUpdateRequest.php
@@ -0,0 +1,36 @@
+<?php namespace App\Http\Requests\App;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class CategoryUpdateRequest extends FormRequest
+{
+    /**
+     * Determine if the user is authorized to make this request.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * Get the validation rules that apply to the request.
+     *
+     */
+    public function rules(): array
+    {
+        return [
+            'name' => ['nullable', 'string', 'max:100'],
+            'description' => ['nullable', 'string', 'max:225'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'name.string' => 'El nombre debe ser una cadena de texto.',
+            'name.max' => 'El nombre no debe exceder los 100 caracteres.',
+            'description.string' => 'La descripción debe ser una cadena de texto.',
+            'description.max' => 'La descripción no debe exceder los 225 caracteres.',
+        ];
+    }
+}
diff --git a/app/Http/Requests/App/InventoryStoreRequest.php b/app/Http/Requests/App/InventoryStoreRequest.php
new file mode 100644
index 0000000..b99129e
--- /dev/null
+++ b/app/Http/Requests/App/InventoryStoreRequest.php
@@ -0,0 +1,62 @@
+<?php namespace App\Http\Requests\App;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class InventoryStoreRequest extends FormRequest
+{
+    /**
+     * Determine if the user is authorized to make this request.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * Get the validation rules that apply to the request.
+     *
+     */
+    public function rules(): array
+    {
+        return [
+            // Campos de Inventory
+            'name' => ['required', 'string', 'max:100'],
+            'sku' => ['nullable', 'string', 'max:50', 'unique:inventories,sku'],
+            'category_id' => ['required', 'exists:categories,id'],
+            'stock' => ['nullable', 'integer', 'min:0'],
+
+            // Campos de Price
+            'cost' => ['required', 'numeric', 'min:0'],
+            'retail_price' => ['required', 'numeric', 'min:0', 'gt:cost'],
+            'tax' => ['nullable', 'numeric', 'min:0', 'max:100'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            // Mensajes de Inventory
+            'name.required' => 'El nombre es obligatorio.',
+            'name.string' => 'El nombre debe ser una cadena de texto.',
+            'name.max' => 'El nombre no debe exceder los 100 caracteres.',
+            'sku.string' => 'El SKU debe ser una cadena de texto.',
+            'sku.max' => 'El SKU no debe exceder los 50 caracteres.',
+            'sku.unique' => 'El SKU ya está en uso.',
+            'category_id.required' => 'La categoría es obligatoria.',
+            'category_id.exists' => 'La categoría seleccionada no es válida.',
+            'stock.min' => 'El stock no puede ser negativo.',
+
+            // Mensajes de Price
+            'cost.required' => 'El costo es obligatorio.',
+            'cost.numeric' => 'El costo debe ser un número.',
+            'cost.min' => 'El costo no puede ser negativo.',
+            'retail_price.required' => 'El precio de venta es obligatorio.',
+            'retail_price.numeric' => 'El precio de venta debe ser un número.',
+            'retail_price.min' => 'El precio de venta no puede ser negativo.',
+            'retail_price.gt' => 'El precio de venta debe ser mayor que el costo.',
+            'tax.numeric' => 'El impuesto debe ser un número.',
+            'tax.min' => 'El impuesto no puede ser negativo.',
+            'tax.max' => 'El impuesto no puede exceder el 100%.',
+        ];
+    }
+}
diff --git a/app/Http/Requests/App/InventoryUpdateRequest.php b/app/Http/Requests/App/InventoryUpdateRequest.php
new file mode 100644
index 0000000..e4d5f2f
--- /dev/null
+++ b/app/Http/Requests/App/InventoryUpdateRequest.php
@@ -0,0 +1,58 @@
+<?php namespace App\Http\Requests\App;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class InventoryUpdateRequest extends FormRequest
+{
+    /**
+     * Determine if the user is authorized to make this request.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * Get the validation rules that apply to the request.
+     *
+     */
+    public function rules(): array
+    {
+        return [
+            // Campos de Inventory
+            'name' => ['nullable', 'string', 'max:100'],
+            'sku' => ['nullable', 'string', 'max:50'],
+            'category_id' => ['nullable', 'exists:categories,id'],
+            'stock' => ['nullable', 'integer', 'min:0'],
+
+            // Campos de Price
+            'cost' => ['nullable', 'numeric', 'min:0'],
+            'retail_price' => ['nullable', 'numeric', 'min:0', 'gt:cost'],
+            'tax' => ['nullable', 'numeric', 'min:0', 'max:100'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            // Mensajes de Inventory
+            'name.string' => 'El nombre debe ser una cadena de texto.',
+            'name.max' => 'El nombre no debe exceder los 100 caracteres.',
+            'sku.string' => 'El SKU debe ser una cadena de texto.',
+            'sku.max' => 'El SKU no debe exceder los 50 caracteres.',
+            'sku.unique' => 'El SKU ya está en uso.',
+            'category_id.exists' => 'La categoría seleccionada no es válida.',
+            'stock.min' => 'El stock no puede ser negativo.',
+
+            // Mensajes de Price
+            'cost.numeric' => 'El costo debe ser un número.',
+            'cost.min' => 'El costo no puede ser negativo.',
+            'retail_price.numeric' => 'El precio de venta debe ser un número.',
+            'retail_price.min' => 'El precio de venta no puede ser negativo.',
+            'retail_price.gt' => 'El precio de venta debe ser mayor que el costo.',
+            'tax.numeric' => 'El impuesto debe ser un número.',
+            'tax.min' => 'El impuesto no puede ser negativo.',
+            'tax.max' => 'El impuesto no puede exceder el 100%.',
+        ];
+    }
+}
diff --git a/app/Http/Requests/App/PriceUpdateRequest.php b/app/Http/Requests/App/PriceUpdateRequest.php
new file mode 100644
index 0000000..0bb3885
--- /dev/null
+++ b/app/Http/Requests/App/PriceUpdateRequest.php
@@ -0,0 +1,41 @@
+<?php namespace App\Http\Requests\App;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class PriceUpdateRequest extends FormRequest
+{
+    /**
+     * Determine if the user is authorized to make this request.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * Get the validation rules that apply to the request.
+     *
+     */
+    public function rules(): array
+    {
+        return [
+            'cost' => ['nullable', 'numeric', 'min:0'],
+            'retail_price' => ['nullable', 'numeric', 'min:0', 'gt:cost'],
+            'tax' => ['nullable', 'numeric', 'min:0', 'max:100'],
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'cost.numeric' => 'El costo debe ser un número.',
+            'cost.min' => 'El costo no puede ser negativo.',
+            'retail_price.numeric' => 'El precio de venta debe ser un número.',
+            'retail_price.min' => 'El precio de venta no puede ser negativo.',
+            'retail_price.gt' => 'El precio de venta debe ser mayor que el costo.',
+            'tax.numeric' => 'El impuesto debe ser un número.',
+            'tax.min' => 'El impuesto no puede ser negativo.',
+            'tax.max' => 'El impuesto no puede exceder el 100%.',
+        ];
+    }
+}
diff --git a/app/Http/Requests/App/SaleStoreRequest.php b/app/Http/Requests/App/SaleStoreRequest.php
new file mode 100644
index 0000000..1c653ad
--- /dev/null
+++ b/app/Http/Requests/App/SaleStoreRequest.php
@@ -0,0 +1,79 @@
+<?php
+
+namespace App\Http\Requests\App;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class SaleStoreRequest extends FormRequest
+{
+    /**
+     * Determine if the user is authorized to make this request.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * Get the validation rules that apply to the request.
+     */
+    public function rules(): array
+    {
+        return [
+            // Datos de la venta
+            'user_id' => ['required', 'exists:users,id'],
+            'subtotal' => ['required', 'numeric', 'min:0'],
+            'tax' => ['required', 'numeric', 'min:0'],
+            'total' => ['required', 'numeric', 'min:0'],
+            'payment_method' => ['required', 'in:cash,credit_card,debit_card'],
+
+            // Items del carrito
+            'items' => ['required', 'array', 'min:1'],
+            'items.*.inventory_id' => ['required', 'exists:inventories,id'],
+            'items.*.product_name' => ['required', 'string', 'max:255'],
+            'items.*.quantity' => ['required', 'integer', 'min:1'],
+            'items.*.unit_price' => ['required', 'numeric', 'min:0'],
+            'items.*.subtotal' => ['required', 'numeric', 'min:0'],
+        ];
+    }
+
+    /**
+     * Get custom messages for validator errors.
+     */
+    public function messages(): array
+    {
+        return [
+            // Mensajes de Sale
+            'user_id.required' => 'El usuario es obligatorio.',
+            'user_id.exists' => 'El usuario seleccionado no existe.',
+            'subtotal.required' => 'El subtotal es obligatorio.',
+            'subtotal.numeric' => 'El subtotal debe ser un número.',
+            'subtotal.min' => 'El subtotal no puede ser negativo.',
+            'tax.required' => 'El impuesto es obligatorio.',
+            'tax.numeric' => 'El impuesto debe ser un número.',
+            'tax.min' => 'El impuesto no puede ser negativo.',
+            'total.required' => 'El total es obligatorio.',
+            'total.numeric' => 'El total debe ser un número.',
+            'total.min' => 'El total no puede ser negativo.',
+            'payment_method.required' => 'El método de pago es obligatorio.',
+            'payment_method.in' => 'El método de pago debe ser: efectivo, tarjeta de crédito o débito.',
+
+            // Mensajes de Items
+            'items.required' => 'Debe incluir al menos un producto.',
+            'items.array' => 'Los items deben ser un arreglo.',
+            'items.min' => 'Debe incluir al menos un producto.',
+            'items.*.inventory_id.required' => 'El ID del producto es obligatorio.',
+            'items.*.inventory_id.exists' => 'El producto seleccionado no existe.',
+            'items.*.product_name.required' => 'El nombre del producto es obligatorio.',
+            'items.*.quantity.required' => 'La cantidad es obligatoria.',
+            'items.*.quantity.integer' => 'La cantidad debe ser un número entero.',
+            'items.*.quantity.min' => 'La cantidad debe ser al menos 1.',
+            'items.*.unit_price.required' => 'El precio unitario es obligatorio.',
+            'items.*.unit_price.numeric' => 'El precio unitario debe ser un número.',
+            'items.*.unit_price.min' => 'El precio unitario no puede ser negativo.',
+            'items.*.subtotal.required' => 'El subtotal del item es obligatorio.',
+            'items.*.subtotal.numeric' => 'El subtotal del item debe ser un número.',
+            'items.*.subtotal.min' => 'El subtotal del item no puede ser negativo.',
+        ];
+    }
+}
diff --git a/app/Models/Category.php b/app/Models/Category.php
index 51f9bb1..f06409e 100644
--- a/app/Models/Category.php
+++ b/app/Models/Category.php
@@ -24,4 +24,9 @@ class Category extends Model
     protected $casts = [
         'is_active' => 'boolean',
     ];
+
+    public function inventories()
+    {
+        return $this->hasMany(Inventory::class);
+    }
 }
diff --git a/app/Models/Inventory.php b/app/Models/Inventory.php
index a29630e..4c5c673 100644
--- a/app/Models/Inventory.php
+++ b/app/Models/Inventory.php
@@ -26,4 +26,14 @@ class Inventory extends Model
     protected $casts = [
         'is_active' => 'boolean',
     ];
+
+    public function category()
+    {
+        return $this->belongsTo(Category::class);
+    }
+
+    public function price()
+    {
+        return $this->hasOne(Price::class);
+    }
 }
diff --git a/app/Models/Price.php b/app/Models/Price.php
index b807606..8fed928 100644
--- a/app/Models/Price.php
+++ b/app/Models/Price.php
@@ -27,4 +27,9 @@ class Price extends Model
         'retail_price' => 'decimal:2',
         'tax' => 'decimal:2',
     ];
+
+    public function inventory()
+    {
+        return $this->belongsTo(Inventory::class);
+    }
 }
diff --git a/app/Models/Sale.php b/app/Models/Sale.php
index 094dc40..b3560ad 100644
--- a/app/Models/Sale.php
+++ b/app/Models/Sale.php
@@ -30,4 +30,14 @@ class Sale extends Model
         'tax' => 'decimal:2',
         'total' => 'decimal:2',
     ];
+
+    public function user()
+    {
+        return $this->belongsTo(User::class);
+    }
+
+    public function details()
+    {
+        return $this->hasMany(SaleDetail::class);
+    }
 }
diff --git a/app/Models/SaleDetail.php b/app/Models/SaleDetail.php
index 83fbe73..995eafc 100644
--- a/app/Models/SaleDetail.php
+++ b/app/Models/SaleDetail.php
@@ -28,4 +28,14 @@ class SaleDetail extends Model
         'unit_price' => 'decimal:2',
         'subtotal' => 'decimal:2',
     ];
+
+    public function sale()
+    {
+        return $this->belongsTo(Sale::class);
+    }
+
+    public function inventory()
+    {
+        return $this->belongsTo(Inventory::class);
+    }
 }
diff --git a/app/Services/ProductService.php b/app/Services/ProductService.php
new file mode 100644
index 0000000..8c7572a
--- /dev/null
+++ b/app/Services/ProductService.php
@@ -0,0 +1,62 @@
+<?php namespace App\Services;
+
+use App\Models\Inventory;
+use App\Models\Price;
+use Illuminate\Support\Facades\DB;
+
+class ProductService
+{
+    public function createProduct(array $data)
+    {
+        return DB::transaction(function () use ($data) {
+            $inventory = Inventory::create([
+                'name' => $data['name'],
+                'sku' => $data['sku'],
+                'category_id' => $data['category_id'],
+                'stock' => $data['stock'] ?? 0,
+            ]);
+
+            $price = Price::create([
+                'inventory_id' => $inventory->id,
+                'cost' => $data['cost'],
+                'retail_price' => $data['retail_price'],
+                'tax' => $data['tax'] ?? 16.00,
+            ]);
+
+            return $inventory->load(['category', 'price']);
+        });
+    }
+
+    public function updateProduct(Inventory $inventory, array $data)
+    {
+        return DB::transaction(function () use ($inventory, $data) {
+            // Actualizar campos de Inventory solo si están presentes
+            $inventoryData = array_filter([
+                'name' => $data['name'] ?? null,
+                'sku' => $data['sku'] ?? null,
+                'category_id' => $data['category_id'] ?? null,
+                'stock' => $data['stock'] ?? null,
+            ], fn($value) => $value !== null);
+
+            if (!empty($inventoryData)) {
+                $inventory->update($inventoryData);
+            }
+
+            // Actualizar campos de Price solo si están presentes
+            $priceData = array_filter([
+                'cost' => $data['cost'] ?? null,
+                'retail_price' => $data['retail_price'] ?? null,
+                'tax' => $data['tax'] ?? null,
+            ], fn($value) => $value !== null);
+
+            if (!empty($priceData)) {
+                $inventory->price()->updateOrCreate(
+                    ['inventory_id' => $inventory->id],
+                    $priceData
+                );
+            }
+
+            return $inventory->fresh(['category', 'price']);
+        });
+    }
+}
diff --git a/app/Services/SaleService.php b/app/Services/SaleService.php
new file mode 100644
index 0000000..30e7c61
--- /dev/null
+++ b/app/Services/SaleService.php
@@ -0,0 +1,98 @@
+<?php namespace App\Services;
+
+use App\Models\Sale;
+use App\Models\SaleDetail;
+use App\Models\Inventory;
+use Illuminate\Support\Facades\DB;
+
+class SaleService
+{
+    /**
+     * Crear una nueva venta con sus detalles
+     *
+     */
+    public function createSale(array $data)
+    {
+        return DB::transaction(function () use ($data) {
+            // 1. Crear la venta principal
+            $sale = Sale::create([
+                'user_id' => $data['user_id'],
+                'invoice_number' => $data['invoice_number'] ?? $this->generateInvoiceNumber(),
+                'subtotal' => $data['subtotal'],
+                'tax' => $data['tax'],
+                'total' => $data['total'],
+                'payment_method' => $data['payment_method'],
+                'status' => $data['status'] ?? 'completed',
+            ]);
+
+            // 2. Crear los detalles de la venta y actualizar stock
+            foreach ($data['items'] as $item) {
+                // Crear detalle de venta
+                SaleDetail::create([
+                    'sale_id' => $sale->id,
+                    'inventory_id' => $item['inventory_id'],
+                    'product_name' => $item['product_name'],
+                    'quantity' => $item['quantity'],
+                    'unit_price' => $item['unit_price'],
+                    'subtotal' => $item['subtotal'],
+                ]);
+
+                // Descontar del stock
+                $inventory = Inventory::find($item['inventory_id']);
+                if ($inventory) {
+                    $inventory->decrement('stock', $item['quantity']);
+                }
+            }
+
+            // 3. Retornar la venta con sus relaciones cargadas
+            return $sale->load(['details.inventory', 'user']);
+        });
+    }
+
+    /**
+     * Cancelar una venta y restaurar el stock
+     *
+     */
+    public function cancelSale(Sale $sale)
+    {
+        return DB::transaction(function () use ($sale) {
+            // Verificar que la venta esté completada
+            if ($sale->status !== 'completed') {
+                throw new \Exception('Solo se pueden cancelar ventas completadas.');
+            }
+
+            // Restaurar stock de cada producto
+            foreach ($sale->details as $detail) {
+                $inventory = Inventory::find($detail->inventory_id);
+                if ($inventory) {
+                    $inventory->increment('stock', $detail->quantity);
+                }
+            }
+
+            // Marcar venta como cancelada
+            $sale->update(['status' => 'cancelled']);
+
+            return $sale->fresh(['details.inventory', 'user']);
+        });
+    }
+
+    /**
+     * Generar número de factura único
+     * Formato: INV-YYYYMMDD-0001
+     */
+    private function generateInvoiceNumber(): string
+    {
+        $prefix = 'INV-';
+        $date = now()->format('Ymd');
+
+        // Obtener la última venta del día
+        $lastSale = Sale::whereDate('created_at', today())
+            ->orderBy('id', 'desc')
+            ->first();
+
+        // Incrementar secuencial
+        $sequential = $lastSale ? (intval(substr($lastSale->invoice_number, -4)) + 1) : 1;
+
+        return $prefix . $date . '-' . str_pad($sequential, 4, '0', STR_PAD_LEFT);
+    }
+}
diff --git a/routes/api.php b/routes/api.php
index b752e50..5059e69 100644
--- a/routes/api.php
+++ b/routes/api.php
@@ -1,16 +1,21 @@
 <?php
+
+use App\Http\Controllers\App\CategoryController;
+use App\Http\Controllers\App\InventoryController;
+use App\Http\Controllers\App\PriceController;
+use App\Http\Controllers\App\SaleController;
 use Illuminate\Support\Facades\Route;
 
 /**
  * Rutas del núcleo de la aplicación.
- * 
+ *
  * Se recomienda que no se modifiquen estas rutas a menos que sepa lo que está haciendo.
  */
 require('core.php');
 
 /**
  * Rutas de tu aplicación.
- * 
+ *
  * Estas rutas son de la aplicación AP   I que desarrollarás. Siéntete libre de agregar lo que consideres necesario.
  * Procura revisar que no existan rutas que entren en conflicto con las rutas del núcleo.
  */
@@ -18,6 +23,21 @@
 /** Rutas protegidas (requieren autenticación) */
 Route::middleware('auth:api')->group(function() {
     // Tus rutas protegidas
+
+    //INVENTARIO
+    Route::resource('inventario', InventoryController::class);
+
+    //CATEGORIAS
+    Route::resource('categorias', CategoryController::class);
+
+    //PRECIOS
+    Route::resource('precios', PriceController::class);
+
+    // Rutas que debes agregar en routes/api.php
+    Route::resource('/sales', SaleController::class);
+    Route::put('/sales/{sale}/cancel', [SaleController::class, 'cancel']);
+
+
 });
 
 /** Rutas públicas */