Well this is my thinking on painting and repairing the exterior of a car. Hood,bumper,fenders,bumpers blah blah anything you can bolt off and replace I would. One reason is that if you repair it. Like Jafro said.. it can suck up the paint, get dull, ext. Also your gonna repair the bumper if some dick backs up into your bumper do you know whats the first thing to chip off? That little bit of bondo. I know the OEM parts are crazy $ but you can always get that after market OEM parts. Fenders by me are $39 primed up and ready to paint. But whatever goodluck and I hope this ain't just so mom and pops kinda guy who don't know much.