I paid off my car using multiple payments because they only accept a max of $3,000 increments. I set up 5 payments of $3,000, but they charged me 6 payments. They refuse to take any documentation other than my complete bank statement, even though they can go to my account and see that I only authorized 5 payments, yet they sent me confirmation for 6 payments. I'm taking them to small claims court and having my attorney address the issue.
Don't use them. They will steal your money, then try to make you prove it.