This scam relies on the fact that the US requires money orders to have the money available within a certain number of days. In other words you can actually cash the money order, even though it is bogus. You learn this when the financial institution charges you for the money they paid out, that you were supposed to send to the originator of the scam. If you actually cashed the check, put the money in a high interest account and make a few cents off it before you give it back.
I do this:
I agree to their deal, take the money order and send it to the FBI office in Houston. Then I mail the scammer a cow turd (plenty of them in the pasture next door) I wrap it in bubble wrap, and add a note that says "Bullshit".
Usually they will even let you use their fed ex account to send the turd.
The funny thing is that they ALWAYS contact me and tell me I scammed them. I tell them, "Yeah, and I enjoyed it immensely - how do you like THEM apples?" Done it about ten times now.
BTY you will get the same scam if you try to sell a laptop on Craigslist. Usually, they are travailing overseas, and want to send you money (a lot more than you asked for), and they want you to send the laptop to their daughter or whoever it was. Sometimes they also add money to the total for you to send to the relative along with the laptop. When I respond to the laptop ones, I send them a concrete block in a big box (hey, they EXPECT it to be heavy!). I often wonder how much fed ex charges to ship a concrete block to Nigeria first class ..