IRS claimed I owned them X, I insisted I owed X/2 (or so). I paid what I thought I owed on X/2. After two two years of threats (from the IRS), IRS said I owed less than X/2 and sent me a check for $10K. YAY. Whatever. Buying a house at the same time, the lender demanded that I detail WHERE the money (from the IRS) came from -- my entire reason was "IRS" (doesn't get any more free [unencumbered] than that) ... that was that. Sometimes errors are in your favor. Oh ya, I also had Y deposited into my account (Chase) -- took 2 - 3 years to convince the bank it wasn't really mine. When they finally agreed, they immediately -Y'd my account. Whoosh! BTW: Never seen a bank account at -Y. Y was not small.