(b) The commissioner may authorize the acceptance of a certificate of inspection issued in another state having inspection requirements substantially similar to those of this state. He may also extend, on any reasonable ground, the time within which a certificate shall be obtained by the owner of a motor vehicle.

(c) The commissioner may, consistent with federal law and regulations, permit any person, association, corporation or subsidiary corporation of a parent corporation having registered in his or its name in this state more than twenty-five motor vehicles, and qualified dealers of motor vehicles held by them for sale or demonstration, who maintain approved inspection facilities, to conduct the inspection or inspections required by this article under regulation prescribed by the commissioner.

(d) The commissioner of motor vehicles may appoint and at pleasure remove inspectors, consultants and such other assistants and employees as he may deem necessary, within the amount available therefor by appropriation, to carry out the provisions of this article.

(e) The commissioner is empowered to make reasonable rules and regulations for the administration and enforcement of this article and the periods during which motor vehicles are required to be inspected.

(f) The commissioner of motor vehicles may, consistent with federal law and regulations, upon application of any municipality, and upon a determination that such municipality has sufficient personnel and approved inspection facilities to conduct the inspection or inspections required by this article under the regulations prescribed by the commissioner, permit such municipality to conduct the inspection required by this article.