This is called the Nigerian Net Scam Version 3. This refers to an American published article - however the final paragraph in red seems relevant to all transactions.

The article reads:
All those beleaguered widows, complaining chief's sons and yowling
high-ranking government officials don't want your assistance in getting a
large sum of money out of Nigeria anymore.
Now they want to buy your stuff.
Yes, there's a new twist in Nigeria's thriving Internet-based scam
operations. This time, the scammers pose as potential buyers for big-ticket
items, like cars, listed for sale online.
The buyer explains that a business associate in the United States will mail
the seller a cashier's check for the amount of the item plus the cost to
transport it overseas. The seller is asked to wire the transportation fees
to the buyer once the check has cleared so the buyer can arrange for shipment. But a week or so after the check clears and the money has been wired,
victims are notified by their banks that the check was counterfeited. The scam has become so widespread that victims formed their own online
support group last month. The group now has close to a hundred members. Scam victims admit they initially were skeptical when the deal was
brokered, but after receiving and depositing a cashier's check that
cleared, they assumed all was well.
The scam takes advantage of a little-known loophole in the U.S. banking
system. Many people don't realize that when a bank says funds have cleared,
it doesn't mean the check is good, according to Carol McKay, director of
communications for the National Consumers League.
"Under federal law, depending on the type of checks deposited, banks must
give consumers access to the money within one to five days. Longer holds
can be placed on deposits over $5,000, but banks are reluctant to
inconvenience their customers," McKay explained. "Unfortunately, it can take weeks for fake checks to be detected in the
banking system. And consumers are then left holding the bag for the money
they've withdrawn. That's because it's the depositor, not the bank, who is
responsible if a check turns out to be bad."
Jeff and Shawn Mosch were victims of the scam, and they figure their bank
is just as much at fault as the con artist who ripped them off for $7,200. Shawn Mosch said she went to the bank with the cashier's check and told the
teller, "I need to know when this is going to be a good, clear check --
when this is going to be actual money I can spend and it's never going to
come back and bite me in the butt."
She was told her butt would be out of harm's way in 24 hours. Mosch said she waited an extra day just to make sure, and then wired the
money to the buyer. Five days later, the bank informed Mosch the check was
counterfeit and her checking account was now $5,000 overdrawn. McKay said the scam isn't limited to Internet sellers. The Consumers League
is starting to hear from people who have also received counterfeit checks
in connection with work-at-home offers.
"Banks would serve their customers better by explaining that they can't
immediately tell if the checks are good and that the depositors will be
stuck if they're not," McKay said. "In general, it's probably a good idea
to wait several weeks before drawing on checks from unfamiliar sources. "But the bottom line is this: No legitimate company will offer to pay you
by arranging to send you a check and asking you to wire some of the money
back. If that's the pitch, it's a scam."

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