I run http://builtFromIdeas.com, where I build apps, generally for non-tech entrepreneurs, for $5,000. I've had a few clients "succeed" without continued input from me. I consider success a lifestyle business, where income each month was at least enough to move onto the next venture. With a well-built app and enough knowledge of your vertical and marketing, it's definitely do-able. At this writing none of them are millionaires.