Jon Hunt, who who earlier this year sold the Foxtons estate agency for £390mi, is to give his own property an extraordinary makeover. The Sunday Telegraph

Hunt, 54, has ordered a vast subterranean extension dug 15 metres (50ft) beneath the lawn at the Kensington Palace Gardens property, creating space for a cavernous sports hall, large enough for a tennis court, for his wife Lois and their four children.

Above, is a swimming pool, gym, sauna and steam room, as well as an area, described on planning documents as a ‘car museum’, where Hunt will display his six classic Ferraris.

The cost of the subterranean scheme beneath the seven-storey, eight-bedroom grade II-listed house will dwarf the £14m originally paid for it.

An architect who has studied the plans in detail said: ‘We’re talking tens of millions, not millions.’