I have learned the areas that spending money on wont be an absolute waste. An exhaust system... Not a waste, a paint job, wont get ur money back. Its common sence, also depends on the car.
Someone who puts the money and time into that is a loser, i have seen them roll around too, lol. Nun special bout them at all. Mindaswell jus get an S2000 lol
You won't get back the money you spend to upgrade most cars guys. It is pretty much like throwing your money in a toilet (don't get me wrong, I think most civics are gay).