You need to learn how to ask the proper question without public intention of racial discrimination.
Carefully read contingencies in your purchase contract. Usually, you can back out the deal in the contigencie of (1)inspection, (2)market appraisal, and (3) loan.
Just do whateve you feel comfortable. You wont be happy do what you are forced to do. You cannot get enough rental payment to compensate for you suffering. It is not worth if you worry all the time.
I can easily found very fine black people in our a few rental property communities and become acquaitance with them. They are willing to give me help during remodeling the houses and moving large appliances. Some of my black tennats are very decent and always pay rental on time. Other give me a little trouble but are still reasonable. The recent most troubling cases I have seen and heard among my friends and myself are with Asian and white people.
Certainly, you need skill to screen the troubling people out, not only among black, but among other races as well. Your scare is totally unjustified simply based on races. It is sad to find out that our Chinese are the group with the strongest race discrimination in public.