The commissioner of commerce and insurance is empowered to set standards for constructing and installing modular building units and to provide for their inspection. No local standard relative to modular building units shall be effective unless it is identical to one established by the commissioner. A city may make inspections and charge a fee only if the local standard is identical. The fee must be equal to the fee for similar inspections of conventional housing. Any modular building unit bearing an approval insignia issued by or on behalf of the commissioner shall be deemed to comply with any local standard. Local zoning requirements, fire zones, subdivision control, and aesthetic requirements are reserved to cities, but they must be reasonable and uniformly applied. The commissioner may delegate inspection authority to local governments. T.C.A. §§ 68-126-303 and 304.