John Caudwell is getting the hang of speaking like a property mogul.

The tycoon, who became a billionaire when he sold mobile-phone businesses including Phones4U, the retailer, in 2006, casually reels off the superlatives about his latest project, a block of luxury flats in Mayfair: it will be “the world’s most expensive and prestigious apartment block”; “it’s prime real estate done to the highest possible standard”.