The plans for the new office building show the size of the office to be 5,200 square feet. The average price has been estimated $120 per square foot according to the industry standards. The following average cost information is available from contractors: 24 % Excavation and framing complete 8% Roof complete 3 % Wiring roughed in 4 6% Plumbing roughed in 5% Siding on 17% Windows, insulation, walks and plaster complete 9% Furnace installed 4 % Plumbing fixtures installed 10 % Exterior paint, light fixtures installed, finish hardware installed 6% Carpet and trim installed 4% Interior decorating 4% Floors laid and finished What is the estimated cost for the office if the company uses contractors to complete the entire work