Before I buy or sell to someone I don't know, I check their posts.
Are they part of the community or just camping in the classifieds and working deals.
Communicate all the way through the sale and make a new buddy, it's not that hard.
"Camping places fix themselves in your mind as if you had spent long periods of your life in them. You will remember a curve of your wagon track in the grass of the plain like the features of a friend." Isak Dinesen