diff --git a/run_tests.sh b/run_tests.sh
index 0e146b6..73a02c5 100755
--- a/run_tests.sh
+++ b/run_tests.sh
@@ -1,4 +1,4 @@
 _#!/bin/bash
 export PYTHONPATH=./
-rm -rf db.sqlite
+rm -rf db.sqlite3
 pytest
\ No newline at end of file
diff --git a/test/test_example.py b/test/test_example.py
deleted file mode 100644
index 4b61d2e..0000000
--- a/test/test_example.py
+++ /dev/null
@@ -1,6 +0,0 @@
-
-# content of test_sample.py
-
-def test_equality():
-
-    assert 1==1
\ No newline at end of file
diff --git a/test/test_models.py b/test/test_models.py
new file mode 100644
index 0000000..f47f135
--- /dev/null
+++ b/test/test_models.py
@@ -0,0 +1,63 @@
+import pytest
+from django.contrib.auth import get_user_model
+from inventory.models import Product, Order, OrderItem
+
+User = get_user_model()
+
+@pytest.fixture
+def user():
+    return User.objects.create_user(
+        username='testuser',
+        password='password123',
+        email='testuser@example.com'
+    )
+
+@pytest.fixture
+def admin_user():
+    return User.objects.create_superuser(
+        username='adminuser',
+        password='adminpassword',
+        email='admin@example.com'
+    )
+
+@pytest.mark.django_db
+def test_product_creation(user):
+    product = Product.objects.create(
+        name='Test Product',
+        description='Test Description',
+        quantity=100,
+        price=10,
+        owner=user
+    )
+    
+    assert product.name == 'Test Product'
+    assert product.description == 'Test Description'
+    assert product.quantity == 100
+    assert product.price == 10
+    assert product.owner == user
+
+
+@pytest.mark.django_db
+def test_order_creation(user):
+    order = Order.objects.create(owner=user, status='pending')
+    
+    assert order.owner == user
+    assert order.status == 'pending'
+    assert order.items.count() == 0
+
+
+@pytest.mark.django_db
+def test_order_item_creation(user):
+    product = Product.objects.create(
+        name='Test Product',
+        description='Test Description',
+        quantity=100,
+        price=10,
+        owner=user
+    )
+    order = Order.objects.create(owner=user, status='pending')
+    order_item = OrderItem.objects.create(order=order, product=product, quantity=10)
+    
+    assert order_item.order == order
+    assert order_item.product == product
+    assert order_item.quantity == 10
diff --git a/test/test_serializers.py b/test/test_serializers.py
new file mode 100644
index 0000000..fcc15b2
--- /dev/null
+++ b/test/test_serializers.py
@@ -0,0 +1,115 @@
+import pytest
+from rest_framework.exceptions import ValidationError
+from inventory.models import Product, Order, OrderItem
+from inventory.serializers import OrderSerializer, OrderItemSerializer
+from django.contrib.auth import get_user_model
+
+User = get_user_model()
+
+@pytest.mark.django_db
+def test_order_item_serializer():
+    user = User.objects.create_user(username='testuser', email='admin@mail.com', password='password')
+    product = Product.objects.create(name='Test Product', description='Test Description', quantity=100, price=10, owner=user)
+    order = Order.objects.create(owner=user, status='pending')
+    
+    data = {
+        'product': product.id,
+        'quantity': 10
+    }
+    
+    serializer = OrderItemSerializer(data=data)
+    assert serializer.is_valid()
+    item = serializer.save(order=order)
+    
+    assert item.order == order
+    assert item.product == product
+    assert item.quantity == 10
+
+@pytest.mark.django_db
+def test_order_serializer():
+    user = User.objects.create_user(username='testuser2', email='admin2@mail.com', password='password')
+    product = Product.objects.create(name='Test Product2', description='Test Description', quantity=100, price=10, owner=user)
+    
+    data = {
+        'status': 'pending',
+        'items': [
+            {
+                'product': product.id,
+                'quantity': 10
+            }
+        ]
+    }
+    
+    serializer = OrderSerializer(data=data)
+    assert serializer.is_valid()
+    
+    order = serializer.save(owner=user)
+    
+    assert order.owner == user
+    assert order.status == 'pending'
+    assert order.items.count() == 1
+    
+    item = order.items.first()
+    assert item.product == product
+    assert item.quantity == 10
+    
+
+@pytest.mark.django_db
+def test_order_serializer_invalid_product():
+    user = User.objects.create_user(username='testuser3', email='admin3@mail.com', password='password')
+    
+    data = {
+        'status': 'pending',
+        'items': [
+            {
+                'product': 999,  # Invalid product ID
+                'quantity': 10
+            }
+        ]
+    }
+    
+    serializer = OrderSerializer(data=data)
+    assert not serializer.is_valid()
+    assert 'items' in serializer.errors
+
+
+@pytest.mark.django_db
+def test_order_serializer_insufficient_stock():
+    user = User.objects.create_user(username='testuser4', email='admin4@mail.com', password='password')
+    product = Product.objects.create(name='Test Product3', description='Test Description', quantity=5, price=10, owner=user)
+    
+    data = {
+        'status': 'pending',
+        'items': [
+            {
+                'product': product.id,
+                'quantity': 10
+            }
+        ]
+    }
+    
+    serializer = OrderSerializer(data=data)
+    assert serializer.is_valid()
+    
+    with pytest.raises(ValidationError) as excinfo:
+        serializer.save(owner=user)
+    
+    assert 'Insufficient stock' in str(excinfo.value)
+
+@pytest.mark.django_db
+def test_order_serializer_partial_update():
+    user = User.objects.create_user(username='testuser5', email='admin5@mail.com', password='password')
+    product = Product.objects.create(name='Test Product4', description='Test Description', quantity=100, price=10, owner=user)
+    order = Order.objects.create(owner=user, status='pending')
+    OrderItem.objects.create(order=order, product=product, quantity=10)
+    
+    data = {
+        'status': 'completed'
+    }
+    
+    serializer = OrderSerializer(order, data=data, partial=True)
+    assert serializer.is_valid()
+    
+    updated_order = serializer.save()
+    assert updated_order.status == 'completed'
+    assert updated_order.items.count() == 1