THE property market may be sliding into the doldrums, but someone forgot to tell a small patch of north London.

Toprak Mansion on The Bishop’s Avenue, Barnet, sold last week for £50m, breaking a record for a newly built property which was set only two weeks ago by a nearby house called Palladio, which was sold for £35m. The name of the Toprak purchaser was given as Horelma Peramam, a billionaire from Kazakhstan.

Toprak Mansion was built by Halis Toprak, a Turkish businessman, although it is understood that he has never lived there. He sold up after his bank was seized by the Turkish government.

It was marketed discreetly for several years, and the asking price climbed from £30m to £50m as prime residential London prices soared. The house had been nicknamed Top Whack Mansion but will now be known as Royal Mansion.

The Bishop’s Avenue, a street of super-sized mansions, is known as “Billionaires’ Row”. The Sultan of Brunei and the Saudi Arabian royal family own a number of properties there.

Toprak Mansion itself is one of two houses built on a plot of land that was left empty after squatters burnt down the previous house.

The other property is the Summer Palace, owned by Lakshmi Mittal, the steel baron, although he spends most of his time at his other home in Kensington Palace Gardens, west London.

The neo-classical Toprak, with a green copper roof and Grecian-style pillars at the front, sits in two acres of garden and boasts a main salon that is 80ft long with a 30ft dining table, a Turkish bath that can accommodate 20, a swimming pool with a glass bridge and four separate kitchens.

The purchaser intends to spend up to £30m on a revamp by a top Italian designer, as well as installing a beauty salon, spa, heliport, cinema and squash court.

Trevor Abrahamson, managing director of Glentree Estates, the estate agent, sold both Toprak Mansion and Palladio. “It is another record amount, but the purchaser thinks it is a very reasonable figure for this sort of house,” he said.

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