When is an office an office? If you are a D.C. real estate broker and you hang your license on the wall of a telephone-answering service, can you call that office your place of business?

This weighty question now rests on the table at the D.C. Real Estate Commission, whose decision sometime this month could affect dozens of city real estate brokers.

The question of what constitutes a legal real estate office was raised by Don J. Edwards, recently appointed member of the board of commissioners. Shortly after joining the board, Edwards requested "a full and complete investigation concerning D.C. real estate brokers who may be using illegal offices." It was time, Edwards told the commission, for the board to define clearly what the 1937 D.C. real estate code means by a "place of business."

After Edwards' request, commission investigator Robert Britt visited the office of Sincerely Yours Inc., a Capitol Hill answering service, and reported finding 14 real estate brokers' licenses on the wall and one on a table near the switchboard. The answering service is at 325 Pennsylvania Ave. NW.

Britt said he recorded the names of the 13 individual brokers and the two realty companies and checked them against records in the D.C. Office of Licenses and Permits. Britt said he found that all the real estate licenses were District residents.

If a real estate broker lives in the District, he must have an office in the District, according to Daniel Osborne, chief investigator for the D.C. Office of Investigation and Enforcement.

The District Code states, "Every (licensed) broker . . . shall maintain a place of business in the District of Columbia need not maintain a place of business within the District of Columbia if he is licensed in and maintains a place of business in the state in which he resides."

On the question of what constitutes a legal office, Osborne, said, "The whole case will lie on what the board determines is a place of business." He added, "My interpretation of 'a place of business' is an office with a desk, a phone, a secretary or someone there between 9 and 5 -- normal business hours -- and a broker or agent there to serve to the public."

Britt reported that only one of the brokers who display their licenses at the answering service maintains an adjacent office where the broker can be reached during business hours.

The other 14 brokers share a second adjacent office, and must make appointments with the answering service to use it when they need to see clients, Britt said.

Saying he doubts the effectiveness of such a setup, Osborne added, "If five people came in to see five different brokers (all at once), what would happen? The public could not be fairly served."

Edwards said that such a setup does not reflect positively on the D.C. real estate business.

Osborne said real estate brokers who use the answering service "to barely meet the letter of the law" are, in his opinion, "circumventing the law."

Real estate brokers and answering service operators disagree.

"I personally don't see what the problem is; the Realtors do indeed have an address and an office," said Joyce Gray, owner of Sincerely Yours, who operates three other answering services in the District and Maryland.

Gail Greene, manager of the Captol Hill office, said the brokers pay up to as much as $100 a month to receive telephone calls and mail at the answering service address and to use the adjoining office, which is equipped with a telephone, a desk and a file cabinet.

Joel Truitt, of Truitt and Associates, is one of the brokers who uses the answering service as his office."I don't use my broker's license very much," he said. "We're primarily a construction company. We buy and sell property which we restore ourselves."

Pruitt said, "We're legal in every sense of the word."

Osborne said the prestige of having a Capitol Hill address and the low monthly rates probably make using the answering service appealing to many small real estate businesses and independent brokers who are just starting out. Pruitt, who lives on Capitol Hill, said he has used the service for more than 10 years because its location is convenient.

"Answering services have always rented out extra space to offer to beginning Realtors and small businesses," said Gray, whose company serves approximately 45 brokers in the District.

"Brokers may have been using answering services for regular offices since 1937, but what was good in 1937 may not be good today," Edwards said.

The real estate commissioners as well as many government officials and District residents, recently voiced support for legislation that would update and revise the 1937 code. The City Council has the question under consideration.