:^/ Another approach might be to start out small. Acquire the appropriate hardware and software to flash a selected range of phones, and then freelance out to existing shops. If your equipment is portable enough, you could even travel to a shop, flash the phones that they've set aside for you, then continue on to the next shop on your list.

Invest whatever profits you get into expanding your capabilities. While you're making the rounds of the town, you'll also get a feel for which neighborhoods get the most business, etc. Take notes as you go so you'll be well prepared when you're ready to make the leap into your own storefront.