Each nonresident owner of a motor vehicle, trailer, or semitrailer applying for the registration thereof in the Commonwealth shall file with the application a duly executed instrument, constituting the Commissioner and his successors in office his attorney on whom all lawful process against and notice to the owner may be served in any action or legal proceeding brought as the result of the operation or use of any motor vehicle, trailer, or semitrailer registered by or for him, in the Commonwealth; and therein shall agree that any process against or notice to the owner shall have the same effect as if served on the owner within the Commonwealth. The service of the process or notice shall be made by leaving a copy of it in the office of the Commissioner with a service fee of three dollars to be taxed as a part of the costs of the suit. The Commissioner shall forthwith notify the owner of the service by letter.