defective flat roof

We were recently instructed to carry out a Valuation on a terraced commercial unit in Tooting, London. The property has been poorly maintained and is in need of total refurbishment. The flat roof is in particularly poor order and the lack of care taken over the building has lead to the major leak evident in the photo below. It is vital that owners/tenants try to maintain their properties to avoid major remedial works and prolong the useful working life of the building.