His wife Lady Bearsted worked with "Kitty" Lloyd Jones to transform the house's garden during the early 1930s.

In October 1991, she offered for sale by public auction, a large number of items which were considered surplus to requirements.

The sale, by Christie's, took place at the house, in a total of 1083 separate lots, and included pictures, furniture, porcelain, silver, objects and carpets.

[12] Perhaps uniquely among country houses owned by the National Trust, its significance lies principally in its art collection.

[13] It contains a unique Art Deco bathroom and a collection of early Shell advertising posters, together with some of their original artwork, by such artists as Rex Whistler.

[14] The collection at Upton includes English and Continental old masters such as: Giovanni Battista Tiepolo, Anthony Devis, Francesco Guardi, Jan Steen, Melchior d'Hondecoeter, Thomas Gainsborough, Joshua Reynolds, Tintoretto and Rogier van der Weyden.

[14] The room also contains a set of dining chairs embroidered by Marcus Samuel, 3rd Viscount Bearsted, as a means of rehabilitation to recover from injuries received during the Second World War.

A series of display cases designed by Percy Richard Morley Horder[20] also showcase a range of English porcelain from Chelsea, Derby and Bow as well as the French factories in Vincennes as Sèvres, predominately featuring Rococo figures and decorative objects.