I was baited into $220 in unexplained fees. I switched my auto-pay from one bank to another. I did my due diligence of double, triple checking the account/routing information. Payment typically being removed on the 1st, I called on the 2nd to see if everything was ok and to verify they had the correct numbers. For whatever reason, the payment company Aimco, claimed that they could not see the account number for verification, but just to call back Monday (the 5th) because it was probably just taking the weekend to process. Well Monday rolls around and they tell me that the payment was returned for Invalid Account Number Structure (along with a $40 fee), but they can't tell me what account number they used. And it was nice of them to suggest calling back on Monday, because now I owe them a $150 late fee, plus $30 to pay it back by card. Oh, and here's a nice ending to the letter: "This payment must be made within 48 hours. After the expiration of this period of time, this matter will be referred for legal action." They still won't tell me what account they charged, insist it's user error, but will provide nothing to substantiate that.