That is just plain mean to waste their valuable time. Scammers are people too.
I had a list of parts I put up for sale. Someone wanted to buy all of them. You want to buy the lot and you don't negotiate? BS. Oh, you are going to send me a cashier's check for OVER THE AMOUNT and send the balance to your friend in BFE? Sure. Fedex next day from Nigeria? NP. I got it and ran the tracking number and sure enough, Nigeria. I emailed the guy with the sad news that Fedex left the envelope in a bad area and it got soaked. NP, they would send me another check. WOW!! Exactly the same cashier's check? NO ****. Called him this time to tell him that the check was not honored by the bank and if he wanted, he'd have to send another one or a wire transfer to my bank account.