Ed Mead, of Douglas & Gordon, said: "The most likely gazunderer will be an investment banker, in fact anyone in the City, particularly a single bloke looking to show off to his girlfriend or vice-versa. It's reasonable to expect people to negotiate say £10,000 to £15,000 for issues such as damp but if the buyer is trying to get 10 to 15 per cent off, then you're into gazundering territory."