 profit on the sale of his house. This has nothing to do with the mortgage, but it has to do with what you paid for, any major improvements that you put into it, any additions that you put in the house, and that's your profit. And then you have, if you're single, you have $250,000 of tax-free profit. If you're married, it's half a million dollars. And you have to, the caveat there is you have to have lived in the house, been your primary residence for two out of five years.