It also built trams for the State Electricity Commission of Victoria's Ballarat, Bendigo and Geelong systems. In 1913 the business was incorporated into a limited liability company in keeping with its increasing scope. In 1919 the company decided to abandon coachbuilding and confine itself to automotive manufacture. In 1900 Duncan & Fraser completed its first automobile body for Lewis Cycle Works. In May 1903 Duncan & Fraser secured the Oldsmobile automobile agency. A showroom, complete with a salesman, spare parts, accessories, clothing and driving instruction was established, a first for South Australia. In 1906, the existing factory was replaced by a new two storey factory. After Duncan died on 2 July 1908, the business was taken over by his four sons, James, Robert, Archie and Richard. Duncan & Fraser secured more automobile agencies, including the Orient Buckboard, Argyll, Standard, Singer, Chalmers and BSA. In August 1909, it secured the sole distributorship for the Ford Model T for South Australia and Broken Hill. The Ford Motor Company in Canada was unhappy about most of the Australian Ford distributors selling other makes. Thus Duncan & Fraser annexed the Ford agency. In October 1920 Duncan Motors was formed to sell and service all Ford products with Duncan & Fraser selling all other makes. In the early 1920s Duncan & Fraser secured the Studebaker car agency. The Kilkenny site was sold to Holden Motor Bodies and a new factory specially designed to manufacture cars built in Mile End. Rectangular in shape, it allowed for an assembly line type process, similar to the system implemented in 1913 by Henry Ford in Detroit to manufacture the Ford Model T. On 21 February 1923, the Franklin Street factory was destroyed by fire. Temporary buildings and workshops were rented in various parts of Adelaide. A new three storey factory opened on the Frankilin Street site in August 1924. In March 1925 the Ford Motor Company of Australia was formed in Geelong, with bodies initially built by Duncan & Fraser and supplied through Duncan Motors. By May 1926 body panels were being imported by Ford Australia directly from Ford Canada and assembled in Geelong. In August 1927, Ford Canada announced that production of the Ford Model T would cease. Ford Australia followed suit a week later. All the Ford agents including Duncan Motors were informed that they would not have any Ford cars to sell for an estimated 12 months whilst the factories in retooled for the new Model A.  Faced with no Ford bodies to build and no Fords to sell and because Duncan & Fraser's other car agencies were unprofitable the directors decided to recommend to the shareholders that the business be wound up.