We helped our DS sell a bunch of household items and furniture on FB Marketplace when the buyers of his house decided 2 weeks before closing that they did not want all the furniture and items that they initially said they did. DH had already moved what he wanted and what would fit down to his new house in Florida and we had to move the remainder of the items out of the old house fast. We had so many people seem very anxious to buy the stuff, set up a time to come, then never show up -or they would show up hours later and wonder why nobody was home. DH and I had to drive 30 mins to meet the buyers at DS's house and it really ticked us off that they would do such things. Very frustrating!
A couple who were buying a big rather expensive item said they couldnt get the cash but would do an e-transfer (Canadian form of Venmo) as soon as they loaded it on their trailer. DH had an uneasy feeling and said no, it isnt leaving the house until you transfer the money. They were adamant that they needed to load it first to make sure it fit (we could see it would easily fit). I was on the phone with our DS while he waited the transfer to go through and sure enough the first transfer didnt, but the guys were starting to carry the item out as soon as the guy hit send on his phone. DS told me to halt them as the money didnt go through which we did, then they did 2 transfers of half the amount each, presumably from different accounts, and those went through.
~Diane