Tires and wheels are a great way to increase the proformance of the vehicle and the over all look. Considering most cars come w/ barely comparable factory wheels.
Second if a paint job or wash>clay>polish>wax is needed do so since most new cars come w/ an obscene amount of contaminents on the paint surface. The "new car smell" is a good example: it's a gas release from the new vinyl interior and can eventually cause the interior glass to become foggy if not maintained. Plus I don't trust a dealer's ability to do a quality detail job before a sale.
3rd I'd say work on what protects the engine before increasing it's proformance directly. ie. Cool air intake, NO OBNOXIOUS MUFFLERS!( if you want the same effect save yourself the money and take the thing off and run w/ just a straight pipe usually increasing HP by 15). I prefer working on the cooling system before I increase any work the engine has to do.
Overall simple elbow grease and detailing will teach you about your car and hopefully tell you what needs replaced, and what your car is missing to make it feel like a New Car or better protect and plan for a New Car purchase.
Good Luck!
