You'd still have to feed it wood most of the night. Have you considered a pellet cooker? Folks are coming up with ways to get more smoke flavor out of them, and they're set-it-and-forget-it, so it would be hard to go wrong there. Also, there are some good gravity-fed charcoal smokers that regulate well - according to other folks - but I don't have any experience with them. But the last thing I would want to do is tend a fire all night and run a business all day. That would get old fast! Good luck in whatever you decide to do!
The Cosmic Pig BBQ
Smokey Joe Silver