There is another aspect; basically, if something is sold at so much less than its market value, unless there is a reason such as a pressing need to collect funds quickly to pay off other debts, the inland revenue smell foul play. They may think it is a way to donate something without having to pay tax on the gift (like if you donate something and then die within 7 years it attracts death duty). They may even claim that your friend has not divested himself of the whole of the property, that he retains some legal interest in the portion of the property he has not been paid for (like �99k if it's worth �199k but he sells for �100k) whereas the purchaser would have, say, legal and beneficial interest in �100k worth of house, beneficial interest only in the �99k worth. So yes, all sorts of problems could arise, like tax liabilities, ability to obtain another mortgage/loans, credit score, etc. The purchaser might have problems with his lender, too. Your friend would be better off putting the house on the market at a realistic, if bargain, price, ready to knock money off say after a month, etc. This way he can show the Inland Revenue that he merely responded to market conditions.