Man in the middle scams are one of the most common when processing payments for parties you are not meeting in person. This is how a Man In the Middle scam works with cash deposits.
Step #1- The scammer finds an innocent party (the man in the middle) who wants to buy something. This can be anything from a car on Craigslist to bitcoins online. He often makes the price so low that the victim is in a rush to complete the deal and is not thinking clearly
Step #2- The scammer finds someone selling bitcoin online and gets the seller’s bank account information.
Step #3- The scammer takes the bitcoin seller’s information and gives it to the buyer stating that is his account.
Step #4- The buyer places money into an account thinking his payment is made
Step #5- The bitcoin seller confirms the money is in his account and releases bitcoin to the scammer.
Step #6- The scammer disappears
Step #7- The buyer/Man In the Middle never receives his merchandise/BTC. He contacts the police and files a report with the bank or payment company.
Step #8- The bank reverses the transaction and the seller loses the money and his bitcoin. The bank often will also close the account of the bitcoin seller.
Step #9- The police investigate and may press charges depending on local laws and the documentation the seller is able to provide.
Great explanation. It works with addresses and cash-in-the-mail ads too, and updating this post to address that possibility would be helpful.