Pete, that's one of the reasons I haven't gone for some of the higher priced "bargains" I've seen. There haven't been many that I was actually considering buying but there have been a few that almost got me. I still don't know if they were real or fake, but when a 3 day (or less) auction comes up with a low ending bid, I have to wonder...
The way I have to find my guns is through reputable people. I would buy from most of the guys here that I've come to know, for example. If a person selling at auction has a store or a lot of good feedback, I'll probably buy from him. I've laid off of good auctions because I doubted the sellers creds.
As Scarlotte (?) said in "Gone with the Wind"... "I've always relied on the kindness of strangers"...