UK's most expensive home: JFK's childhood home

Experts predict Knightsbridge mansion could be worth £287 million

JFK's former house

The London mansion where John F Kennedy lived and worked as a young man could become London's priciest home, after it was bought by a billionaire with big plans for the property.

The Knightsbridge property is a 1840s mansion built for JP Morgan, who gave the property to the US government, to house the US Embassy. It was while it functioned as the Embassy that the future US President lived and worked there in the late 1930s - when his father Joseph was the ambassador. It has seen something of a decline in the intervening years, and by last year it had been converted into offices.

Development plans

The Evening Standard reported that it sold last year for £70 million, and is believed to have been bought by a Saudi billionaire, with plans to convert it into one of the most luxurious homes in London. At this stage it's not known whether the billionaire plans to turn it into one enormous home, or two separate homes - as he has applied for permission to do both.

The newspaper said that plans for development include a huge double basement, which will include two swimming pools, a jacuzzi, gym and changing rooms, kitchen, wine cellar, and staff quarters. On the floor below that there will be underground parking for the family. Incredibly, there will be a separate car entrance for the property, where cars will be driven in at ground floor level, and taken down to the basement by lift.

The ground floor will include a number of grand reception rooms, and the first floor will include a single reception room that stretches the whole length of the property. On the second floor there will be seven bedroom suites, a playroom and a guest sitting room. The whole thing will be accessible by lift.

Most expensive in the UK?

The Daily Mirror reported that estate agents had calculated that the property could become the capital's most expensive home. This is based on the fact that in this incredibly desirable and expensive part of London - overlooking Hyde Park - properties can fetch up to £7,000 per square foot. If this home is turned into a single mega-mansion it would be worth £287 million.

Even if it becomes two properties, there's a chance they could become the two priciest properties, because at £143.5 million they would eclipse the current record holder, the £140 million, 16,000 foot Penthouse of One Hyde Park.

If it remains a single residence, then it will be worth more than the most expensive property currently on the market. Carlton House is a Grade I-listed Regency mansion in the shadow of Buckingham Palace, which was said to have been up for sale on the grey market last year for £250 million.

Much of the talk in recent weeks has been of the shine coming off the London market - including news yesterday that commission earned by Foxtons estate agents was down 25% compared with the same months in 2013. The estate agents are warning of a slowdown in sales, which they expect to last well into the spring. And some are warning that a glut of expensive new homes could continue to depress prices.

However, as those properties show. Once you get into the realms of the utterly ridiculous mega-homes, there's always an international billionaire who will take the property off your hands for an insane sum of money.

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