I almost always offer to do the deal as a CA, (unless the numbers and homeowner's motivation are so great as to make the deal worth remaining in the middle). I offer my expertise, know how, and pro-homeowner agreements as an inducement to the sellers. In short, I pitch what we now know as The Lease Purchase Advantage.
As for which markets, I look for balanced or buyers markets. These days, that means avoiding areas such as where I am in south FL, and many of the major metro areas. Smaller metro areas, in and around the Midwest for example, seem to work well for me.