My favorite is the text or instant message, "would you take $xxx". My standard response is I don't negotiate by email, text, or phone. When would you like to come see it? Call me to set a time.

The only exception is when they are too far away for a come see it trip, and are willing to pick up a phone and have a conversation. Or if they call and are obviously part of the pin community and I get the feeling they are serious. But 42 text or IM messages back and forth, no thanks.

Oh, and second favorite, the "is it still available message" I respond yes, want to come see it? Then they go silent, no response. Have really been tempted to send the FB ones, where you can see their profile, a message on their time line asking why they wasted your time asking if it was still available if they had no intention of responding.