Justins correct here. I've been doing my first few PC cars for about $70, since I'm not the best yet. Once I get better and get away from my friends, I'll charge 200 for paint correction. I didn't touch wheels, tires or interior, but it would really depend on time spent for me.
I don't think you really use too much material when it comes to the correction though. Just a few drops goes a long way.
