Am I the only one?

I have tried to sell one piece of equipment on audiogon. It has been up for a month, and just shortly I renewed my ad because it did not sell. My question is: how many people have had a buyer back out at the last minute? I only ask because this has happened to me three times while selling this one particular piece. It makes me question whether the audiogon buyers are really interested in things, or just want more information about products. The excuse from each buyer was the same. A situation arose, and they were not able to (at the last minute) not able to make the transaction. I get pretty bent out of shape when people say they are interested, ask me to take the time to figure out shipping to their area, and then say something has come up and they can't buy. Anyone else with this situation, or is it just me? What should I do about it?