[yrralis1]

Mods can increase a car's value while others will shy away . I would have to understand what mods as well as the car's history to decide . I'd rather have a stock car driven and pampered by doctor than heavily modded car capriciously driven on the street or track by a playboy . No wonder i have such a hard time selling my cars --lol . Just kidding.

In all seriousness I asked this question to a several used car sales folks over the years --the general answer is 15% of the actual cost of the part plus install . So if someone mods 10K worth add 1500 bucks to what a stock car ought to cost.