Well, not to get ahead of you, but you have to have a house in a good part of town to start demanding things like good credit. Some neighborhoods, you as the landlord are just going to have to take whatever tenents you can get, or let your property sit empty, because the folks with good credit are shopping elsewhere.
Not necessarily so. I own a home in a bad part of town, and have wonderful tenants. They pay their rent on time, and maintain the front yard. They are no trouble whatsoever.