“But then we realized we weren’t apartment people: We had loved having our own front door. And when you hear noise overhead, it’s almost as if it’s in your own place.”

Buyers of original mews homes are often faced with the costs of renovation. While the exteriors tend to retain their period charm, “it is very rare to see any truly original features in mewses, especially in those which have been made fully residential in the last 30 to 40 years,” Mr. Lloyd Malcolm said. “These buildings originally had no flourishes, usually, no cornices, etc., as they were intended for staff and animals.”

He did recall one memorable exception: The last truly original feature he saw was in Hazlitt Mews in 2015, which “still had the stable dividers for an elephant from when the traveling circus came to Kensington Olympia over 100 years ago.”

Ms. Cholmondeley’s two-bedroom, two-and-a-half-bath, late-19th-century mews house also showed evidence of a prior life as a place to store a horse and carriage. The property “needed a lot doing to it,” she said, including raising the ground floor ceiling, replastering throughout, replacing the kitchen, installing skylights and solar panels on the roof, creating an office space and removing a huge semi-industrial spiral staircase that was “the sort of thing you would expect to have in a workshop, not in a private house.”

Their new staircase is her pride and joy, made of hard-wearing bamboo, with storage space underneath.

“We also had to get rid of quite a lot of furniture,” Ms. Cholmondeley said. “You realize that your furniture needs to be on a scale with the size of your property; there’s no point in thinking you can have a great big oak refectory table and chairs.”