just wondering if your car is not completely stock would the price value go down for a trade in at the dealer. for example i have aftermarket headlight and tail lights.

 

I don't think you have to worry about the headlights and tail-lights as long as they are OK by the state's standards. As for heavy modifications like dropping or welding...then you are lookin at losing money...

 

Any extreme changes (welding, shaving etc) you'll lose money. You can crunk some dollars on stock looks (wings, headlights, etc) but don't look to make too much more money off of that. You'll be good as long as what you've done to your car can be undone if a person wants to.