diff --git a/app/api/v1/admin/vendor_domains.py b/app/api/v1/admin/vendor_domains.py
index c3c00755..733cee87 100644
--- a/app/api/v1/admin/vendor_domains.py
+++ b/app/api/v1/admin/vendor_domains.py
@@ -5,7 +5,7 @@ Admin endpoints for managing vendor custom domains.
 Follows the architecture pattern:
 - Endpoints only handle HTTP layer
 - Business logic in service layer
-- Proper exception handling
+- Domain exceptions bubble up to global handler
 - Pydantic schemas for validation
 """
 
@@ -16,10 +16,9 @@ from sqlalchemy.orm import Session
 
 from app.api.deps import get_current_admin_api
 from app.core.database import get_db
-from app.exceptions import VendorNotFoundException
 from app.services.vendor_domain_service import vendor_domain_service
+from app.services.vendor_service import vendor_service
 from models.database.user import User
-from models.database.vendor import Vendor
 from models.schema.vendor_domain import (
     DomainDeletionResponse,
     DomainVerificationInstructions,
@@ -34,26 +33,6 @@ router = APIRouter(prefix="/vendors")
 logger = logging.getLogger(__name__)
 
 
-def _get_vendor_by_id(db: Session, vendor_id: int) -> Vendor:
-    """
-    Helper to get vendor by ID.
-
-    Args:
-        db: Database session
-        vendor_id: Vendor ID
-
-    Returns:
-        Vendor object
-
-    Raises:
-        VendorNotFoundException: If vendor not found
-    """
-    vendor = db.query(Vendor).filter(Vendor.id == vendor_id).first()
-    if not vendor:
-        raise VendorNotFoundException(str(vendor_id), identifier_type="id")
-    return vendor
-
-
 @router.post("/{vendor_id}/domains", response_model=VendorDomainResponse)
 def add_vendor_domain(
     vendor_id: int = Path(..., description="Vendor ID", gt=0),
@@ -122,8 +101,8 @@ def list_vendor_domains(
     **Raises:**
     - 404: Vendor not found
     """
-    # Verify vendor exists
-    _get_vendor_by_id(db, vendor_id)
+    # Verify vendor exists (raises VendorNotFoundException if not found)
+    vendor_service.get_vendor_by_id(db, vendor_id)
 
     domains = vendor_domain_service.get_vendor_domains(db, vendor_id)
 
diff --git a/app/api/v1/admin/vendor_themes.py b/app/api/v1/admin/vendor_themes.py
index 6c45c590..677bff90 100644
--- a/app/api/v1/admin/vendor_themes.py
+++ b/app/api/v1/admin/vendor_themes.py
@@ -21,7 +21,9 @@ from app.api.deps import get_current_admin_api, get_db
 from app.services.vendor_theme_service import vendor_theme_service
 from models.database.user import User
 from models.schema.vendor_theme import (
+    ThemeDeleteResponse,
     ThemePresetListResponse,
+    ThemePresetResponse,
     VendorThemeResponse,
     VendorThemeUpdate,
 )
@@ -51,7 +53,7 @@ async def get_theme_presets(current_admin: User = Depends(get_current_admin_api)
     logger.info("Getting theme presets")
 
     presets = vendor_theme_service.get_available_presets()
-    return {"presets": presets}
+    return ThemePresetListResponse(presets=presets)
 
 
 # ============================================================================
@@ -134,7 +136,7 @@ async def update_vendor_theme(
     # Service handles all validation and raises appropriate exceptions
     # Global exception handler converts them to proper HTTP responses
     theme = vendor_theme_service.update_theme(db, vendor_code, theme_data)
-    return theme.to_dict()
+    return VendorThemeResponse(**theme.to_dict())
 
 
 # ============================================================================
@@ -142,7 +144,7 @@ async def update_vendor_theme(
 # ============================================================================
 
 
-@router.post("/{vendor_code}/preset/{preset_name}")
+@router.post("/{vendor_code}/preset/{preset_name}", response_model=ThemePresetResponse)
 async def apply_theme_preset(
     vendor_code: str = Path(..., description="Vendor code"),
     preset_name: str = Path(..., description="Preset name"),
@@ -184,10 +186,10 @@ async def apply_theme_preset(
     # Global exception handler converts to HTTP 404
     theme = vendor_theme_service.apply_theme_preset(db, vendor_code, preset_name)
 
-    return {
-        "message": f"Applied {preset_name} preset successfully",
-        "theme": theme.to_dict(),
-    }
+    return ThemePresetResponse(
+        message=f"Applied {preset_name} preset successfully",
+        theme=VendorThemeResponse(**theme.to_dict()),
+    )
 
 
 # ============================================================================
@@ -195,7 +197,7 @@ async def apply_theme_preset(
 # ============================================================================
 
 
-@router.delete("/{vendor_code}")
+@router.delete("/{vendor_code}", response_model=ThemeDeleteResponse)
 async def delete_vendor_theme(
     vendor_code: str = Path(..., description="Vendor code"),
     db: Session = Depends(get_db),
@@ -224,4 +226,4 @@ async def delete_vendor_theme(
     # Service handles deletion and raises exceptions if needed
     # Global exception handler converts them to proper HTTP responses
     result = vendor_theme_service.delete_theme(db, vendor_code)
-    return result
+    return ThemeDeleteResponse(message=result.get("message", "Theme deleted successfully"))
diff --git a/models/schema/vendor_theme.py b/models/schema/vendor_theme.py
index 76d823d1..42f8cae9 100644
--- a/models/schema/vendor_theme.py
+++ b/models/schema/vendor_theme.py
@@ -100,3 +100,9 @@ class ThemePresetListResponse(BaseModel):
     """List of available theme presets."""
 
     presets: list[ThemePresetPreview] = Field(..., description="Available presets")
+
+
+class ThemeDeleteResponse(BaseModel):
+    """Response after deleting a theme."""
+
+    message: str = Field(..., description="Success message")