My advice would be to just start small and see what happens. You never know how it's going to work out until you jump in and actually try it. I know I would rather pick up chicks locally than buy them from a hatchery 4 states away. That's partially because the postal service has screwed up my last 2 orders, which resulted in a lot of dead birds, but we won't get into that.
The biggest problem I see is the demand. My husband's cousin breeds Bloodhounds and Airedale Terriers. Sometimes he sells an entire litter in 2 weeks, other years he has to drop the price and then still has trouble selling them, and by that time they're 12 weeks old. Not quite the same situation as selling chicks, but close enough. You don't want to be stuck with forty 3 month old chickens that do nothing but eat feed.
