Other US presidential houses you could look at...
JFK lived at 14 Princes Gate, SW7 as a nipper when his father was ambassador
Martin Van Buren (8th American president) lived at 7 Stratford Place, W1
Dwight David Eisenhower (34th American president) 31 St James's Square and 20 Grosvenor Square
(Courtesy of www.blueplaque.com)
But surely the current ambassador's residence takes the biscuit... Winfield House, set in 12.5 acres of gardens in Regents Park.
Any of you agents out there care to try to put a value on that?