In 1976 Mould founded Arlington Properties alongside business partner Patrick Vaughan. Arlington primarily focused on property developments around
business parks. The company was successful, and listed on the stock exchange in 1986. In 1989,
BAE purchased Arlington Properties for £289m, making Mould a millionaire. Mould continued to work for BAE after the takeover, however in the early 1990's he began Pillar Properties alongside Vaughan once again. Their focus was on the burgeoning market of
retail parks. In 1994, Pillar Properties were stock listed with a value of £170m. In 2005,
British Land, purchased Pillar Properties for £811m. The following year, Mould and Vaughan founded London & Stamford, which merged with the retail landlord Metric Property Investments in 2012 at which time Mould stood down from business. ==Horse racing==