The purpose of this chapter is to promote harmonious intergovernmental relations and encourage sound planning, zoning, and land use practices by prescribing uniform policies and procedures for the Administrator of General Services to acquire, use, and dispose of land in urban areas. To the greatest extent practicable, urban land transactions entered into for the General Services Administration and other federal agencies shall be consistent with zoning and land use practices and with the planning and development objectives of local governments and planning agencies.