Property: On a roll into Mayfair, but not for Monopoly money

MAYFAIR, always the most desirable place to own a house on the Monopoly board, is becoming more attractive in real life. Residential owners are returning to the square of land between Oxford Circus and Hyde Park Corner, which had been lost to offices and absent foreign owners.

Brian d'Arcy Clark, of Chesterfield, estimates that more than 1 million sq ft of space has been converted back into flats and houses. 'Mayfair is definitely more popular with buyers of all nationalities than it has been for a long time,' he says.

One development has just sold, sight unseen, to a Hong Kong buyer. Number 17 Culross Street has been transformed from offices into a deceptively small-looking house. From the outside it looks like a mews with a double garage, as the planners required. Inside is 5,000 sq ft of space, including a 50ft reception room and gym. The house was sold jointly by Wetherell and Lassmans for about pounds 1.75m.

Peter Wetherell, whose firm acts for the Grosvenor Estate, has sold more than 30 office buildings, which have been converted back to homes. 'The thing about Mayfair is that the big house market is back,' he says.

He has sold two houses for pounds 6m each and has a third priced at pounds 5.5m coming up for sale. 'The market goes in cycles,' he says. 'People become more affluent and move farther out. Then they find the travelling too unreliable and inconvenient and move back.

'Rich British people are coming back, but so are the not so rich. You can still buy a one-bedroom flat on a short lease for about pounds 100,000, the same price you pay for a riverside development,' he says.

The most spectacular space on the market is a 15,500 sq ft penthouse shell on the ninth and 10th floors of Fountain House on Park Lane. The space is the equivalent of about 15 semi-detached houses, with another 2,500 sq ft of terraces from which to admire views that stretch to Docklands and over Hyde Park. Garage parking is available for at least 11 cars.

Wetherell has had inquiries from the United States, the Far East and the Middle East as well as Britain. The company is negotiating to sell the property as a whole. If the talks fail, it may be divided into four apartments. 'The property is unique,' Mr Wetherell says.

Another penthouse that has been completed with full security systems and interior design is being sold by Chesterfield and Foxtons. The Penthouse in Down Street has 7,000 sq ft of space, including five bedroom suites and a 60ft reception room. The asking price is pounds 2.9m.