I have done this. I started with my MINI. Then after my parents saw the results they were like 'DO OURS, DO OURS!' (Galant and Altima) so I did theirs. And then a woman that me and my mom worked with saw both of our cars and was like, "DO MINE DO MINE!" (Jetta) So far I've made back $100 of the $280 i spent at DP
As far as branching out into a small business. Unless you are only going to work on friends cars, I would say it'll be more trouble then its worth. And you'd probably need to get some insurance in case you burn the paint and the customer sues. So, if your doing your friends cars, thats cool, go for it. But if your going to be working on strangers cars, think about liability insurance, and think, is it worth it?
