You'd expect a freehold house in swanky Knightsbridge with a 65-foot frontage to sell for tens of millions.
However, this property sold at auction yesterday for just £810,000 - a tiny price by local standards. The reason is that the house is close to two-dimensional, measuring just 2.5 feet wide at its narrowest point.
The mews house has around 275 square feet of space, around the same as a small one-bedroom flat. It's essentially a corridor, around five feet across at its widest point.
Agents Savills Auctions describe it as consisting of a studio room with unfitted bathroom and WC, plus a room where a kitchenette could be fitted.
"The interior requires complete refurbishment, giving the buyer the opportunity to carry out imaginative improvements to their own specification," they say.
However, somebody has seen potential in the space, paying £10,000 more than the guide price.
Is this the UK's narrowest one-storey house?
Until 2010, the property was owned by Linda Wildoner, an Austrian woman who moved there after the Second World War. She worked as a carer for the Poliakoff family before dying at the age of 94.
Is this London's narrowest home: at 99 inches wide?
The sale surely sets a new record for London's narrowest house. It's half the width, for example, of a semi-detached home in Denmark Hill, south-east London, that sold for £450,000 in 2014. The kitchen here is just five feet wide, and the sofa only fits under the stairs - but all the same it sold in a matter of days.
The UK's narrowest home in terms of frontage, according to the Guinness Book of World Records, is the Wedge, in Millport on the Isle of Cumbrae in Scotland. At the front, it measures just 47 inches across - just wide enough for a slimline front door.
However, it widens out at the back, giving room for a bedroom, bathroom, lounge and kitchen area - and sold two years ago for £85,000.
World's narrowest house up for sale: would you pay £85,000 for it?