My sister-in-law had this happen to her.
She was selling a car. Not a great car, but decent. She was hoping for around $1500.
Some guy gets ahold of her via emial stating that he was going to buy a car, but the deal fell through. So he had a money order all made out for $7000. Would she be willing to sell him the car, accept the money order, and then send him back $5000? His agent would be along to collect the cash and the car, as he lives in Texas, works for the UN, and will be out of the country.
She replied “sure! here’s my address.”
Then she called myself and her sister to find out what was up. I told her about the scam. She, ever the optimist, replied that I was just too negative, and maybe this was legit.
Sure enough, a little over a week later a FedEx envelope showed up with a very authentic looking cashiers check written by a bank in, if I recall correctly, Missouri. The mailing address on the FedEx envelope was in Lagos, Nigeria. Imagine my surprise!
She went to her bank and talked to a teller. She stated the deal, and then asked if she could deposit it. They explained that they would deposit it and release some of the funds, but that the rest would have to clear.
She deposited the check, the wrote to her mysterious buyer. She explained what the bank was doing. He wrote back stating that he needed the extra money quite badly for his work, and could she send him a money order for the difference?
She replied that she would do so once the check was fully released, and not before. As a business man, she was sure he would understand. That was the last communication she received from him.
The money order bounced, but as she had essentially treated it like it wasn’t real in the first place, she was alright.