D.C. Mun. Regs. tit. 17, r. 17-2701
Each place of business shall have a phone, desk, and pertinent files and shall conspicuously display therein the license of all persons licensed to act as a broker or salesperson and shall likewise conspicuously display on the door or outside of the premises named in the license a sign bearing the word "Real Estate" or where authorized, "Realtor" or "Realtist." The sign shall be visible from a public highway or public hallway, and shall include the licensee's name. Neither a post office box nor an answering service shall satisfy the requirements of D.C. Official Code § 47-2853.184.
A duplicate real estate broker or property manager license shall be obtained and displayed in each branch office maintained by the real estate broker or property manager within the District.
Each real estate brokerage or property management firm shall be managed by a licensed real estate broker or property manager who shall adhere to the supervision requirements of 17 DCMR 2614 et seq.
Real estate brokers and property managers shall notify the Board of any change in the location of his or her principal place of business upon a form provided by the Board.
The change of address notice required by § 2701.4 of this section shall include the effective date of the relocation and shall be submitted in writing within fifteen (15) days prior to the relocation.
The real estate broker's license and the licenses of all real estate salespersons employed by him or her shall accompany the notice required by § 2701.4 of this section.
Upon receipt of a properly filed notice and payment of fees, the Board shall issue new licenses for the unexpired term within thirty (30) days.
Failure to notify the Board of a change of address or to return the licenses as required by this section shall result in the immediate suspension of the license until the real estate broker or property manager has complied with this section.
D.C. Mun. Regs. tit. 17, r. 17-2701