I've gotten the, "I like your card, will you take such and such amount? .. contact me on Insta.", before.
I essentially responded (paraphrasing), "How the hell to I do that?"
They responded (paraphrasing), "Duh, it's the same handle as my ebay handle".
I actually would have taken their offer and went to the trouble of marking it down just for them on Ebay, but never heard from them again after doing so.