Mayfair has long been the postcode of choice among private equity firms looking for prestigious office space. Close to the best restaurants and members’ clubs, and with the address to impress investors, the area is still in demand with financial firms, but supply is struggling to keep up and some firms are being forced to broaden their search.

Supply of Central London office space fell from 16.5 million square feet in 2012 to 16.1 million square feet at the end of 2013, according to a report on rental rates published by real estate consultancy Knight Frank in February. The vacancy rate fell to 7% - below the 10-year average of 8.5% and its lowest level since the second quarter of 2008.