Back about 15 years ago when Gunbroker was still a relatively new thing I had someone try to do what I assume was a "sting" operation. I had a S&W 4516 for sale and he bid on it and won. As I did with other GB sales I asked him to mail me a copy of a signed FFL so I could ship the gun to that address. He replied that he didn't have an FFL and that I should just put the gun in the mail and send it to him.

He insisted over and over again that it was OK to do this and he also insisted that I send it via US Mail, which makes me think he was likely a postal inspector.

I reported him to GB and re-listed the gun. Kind of wish I'd saved those emails though.