Just go FFL to FFL like is outlined in the rules and that's it. I know there are other ways, but not for sales on this site. It seems not too long ago the entire Classifieds section was almost shut down due to BATF descrepancies and the liability of this site for "promoting" or "hosting" the sales.
It's not worth it to you and definitely not worth jeopardizing this site.
Graybeard puts alot on the line hosting this site, follow HIS rules....irregardless of any interpretations of the law.
I don't want to sound antagonistic or anything, but this site is too awesome to risk losing some of it---or all of it.