D.C. Mun. Regs. tit. 14, § 1201
1201.1 No license to operate an apartment house business shall be issued to a person not a resident of the District of Columbia, unless that non-resident, as a condition of receiving and maintaining the license, does one of the following:
1201.2 A non-resident licensee shall notify the Director of any change in the appointment or employment of his or her attorney-in-fact, general agent, or manager within five (5) business days of the change.
1201.3 In all cases of a non-resident licensee, notice of any action to be taken with respect to the license issued to the licensee may be served upon the attorney-in-fact, general agent, or manager appointed or employed by that non-resident licensee.
1201.4 Upon certification to the Director by an officer of the District required to serve notices in connection with the operation of an apartment house business that a licensee (or the attorney-in-fact, general agent, or manager of that licensee) cannot be found after reasonable search, proceedings against the licensee may be instituted by serving notice, in the manner prescribed in § 105.4 of this title, upon either the licensee or any person who has been designated by the licensee as attorney-in-fact, general agent, or manager, and whose designation has not been rescinded by the licensee in a written notice of rescission sent to the Director.
SOURCE: The Housing Regulations of the District of Columbia, 5G DCRR § 6103, Commissioners' Order 55-1503 (August 11, 1955); as amended by Commissioners' Order 57-1023 (June 6, 1957).