I’d heard a lot about One Hyde Park, the site of the most expensive apartment sold in London, a £160 million penthouse. From the outside, it looks like an upmarket Hilton, but inside, it houses sauna rooms, an ozone swimming pool, a golf simulator, a squash court, room service, and personal panic rooms—all for the bargain price of £7,000 per square foot. One was advertised in 2019 for rent—at £40,000 a week. A majority of the apartments are used as second, third, or fourth homes, and they sit completely empty.

