I sold a high end film scanner years ago. The buyer said he needed it for a project. He used it for a month and then submitted a "not as advertised" and returned it. He didn't follow the rules though when he returned it - forgot to send it with a required signature. You have no idea how tempted I was to say "sorry, I didn't get it...". But the angel on my shoulder won out.

I relisted it and someone else bought it for a few bucks more so it worked out I guess.

Last time I sold something on eBay - not worth the risk.