The cost of a power pole (distribution) transformer depends on rating, voltage class, insulation type and region. Small single phase overhead units for low voltage distribution are far cheaper than large three phase pad mounted designs. Prices are driven by copper and steel costs, insulation system, accessories and certification requirements. Utilities often buy through framework contracts and do not pay «retail» prices. Instead of one fixed number, engineers estimate cost ranges during planning and then obtain project specific quotations that include transport, accessories, testing and warranty conditions.