The Largest Independent Auction, Estate & Letting Agency in the Region with 6 Offices. ::: DDM The Letting Centre manages over 1100 rental properties ::: DDM Property Auction - over 145 properties sold in the first year ::: DDM Financial - an established provider of mortgage and related products Established in 1889, Dickinson Davy and Markham is now known throughout the region as DDM. The biggest asset of DDM Residential is the employees who work in the branches !!!!