RE: How about some ideas...
I do the same thing as Reese. I like to call them on the phone. Then I have their address and phone number. Also, many of these gun sites, the last thing a seller wants is a bad comment. If he is a first time seller, I'd call him and ask him questions about the rifle. Scratches, cracks, trigger pull, hammer, etc.. then you can get an idea as to the kind of person he is. Although there are those out there that are going to get you, and there is little you can do.
I've bought a lot of rifles from auction sites. Only one was a real disappointment. But then it was a "as is" rifle. He just did not make it clear that it was a very poor condition "as is" rifle.