It happened to me at a bicycle shop. I stopped in because I had a flat tire and asked for a new tire and tube.
The counter guy keyed in the wrong number and charged me $488. Then, realizing his mistake, cancelled the charge and recharged me $48.
On my side, I was charged $536. In my account, although the charge was “reversed”, it took me 72 hours to get the use of my money back. (That’s the bank hold time on charges.)
As you can imagine, I wasn’t happy. Aside from the $488 “hold”, the only proof I had was three paper receipts, none of which was for the canelled $488.
Will I ever go back to that shop? Never. Because of the gaff? No. Because of the companies inability to show me they had fixed it before I left. With an online payments processing system, it’s harder to make mistakes and when you do, you get a permanent online record, automatically batched and stored at the end of each day.
I now use a bike shop that’s about 20% more expensive. Why? It’s easy. I trust them.