Fraser Bond are the leading lettings and property management agents for One Stanhope Gate - London W1K. One Stanhope Gate is an office building in Mayfair, London W1. Lothbury Investment Management Limited is adding two additional floors to the building, along with a new rooftop terrace, façade alterations and internal reconfiguration of the ground floor and the cores, with the intention of updating the building for the next stage of its life. An additional seventh floor is being created for the building services. Upon completion, One Stanhope Gate will comprise 35,750 sq ft across six floors of.