I don't think you can be overly paranoid when you have a very keen buyer asking for your private info and the moment it's supplied, he disappears. He was very quick on the communication up until he got the info. If you change your mind, great, say so. It's happened to me often and I send a PM " I think I will pass. Good luck with the sale" Takes 30 seconds and no need feeling bad as we are all behind a keyboard.
Either way, I've done all I can do, willing to give him the benefit of the doubt but he's on my personal "ban list".
The dial has been sold to a long-time member.