H. R. Crawford, a property management executive and former assistant secretary of HUD, said this week that a group he heads has purchased the Trinity Towers apartments (145 units) at 3023 14th St. NW. Crawford said that the price for the 48-year-old building was $224,000. He added that the building had deteriorated badly, is now vacant and will be rehabilitated and rented under a federal subsidy program.

Frances Wallace, an agent with the Chevy Chase office of Begg, Inc., took a brief holiday last week to go to New York City. Mrs. Wallace was asked to play the role of a real estate agent in a segment of the soaper "Search for Tomorrow." Now that's authentic casting. Earlier in her career, Mrs. Wallace had a role in "Mr. Roberts" and did other acting on and off Broadway. She now is wed to a Washington attorney.

Total Management, Inc., headed by Steven H. Bernstein, is handling the conversion to condominium ownership of the four-story MacArthur House, a 29-unit structure in the Cabin John area. Prices range to $38, 750 but only seven of the dwellings are unsold. June Houpert of Bogley, Inc., is handling sales.

A colorful Christmas card from Gulf Reston, Inc., was created by Michelle Luck, 4 1/2, a student at the Reston Town & County School and winner of the pre-school design competition.Green and red, the card has a Christmas look in a contemporary but child-like style. Thanks for the brightener, Michelle.

The Northern Virginia Board of Realtors elected five new officers and one woman (Bobbie Carey) is first vice president. Ten directors were elected and five are women: Patricia Elliott, Mary Howard, Louise Singleton, Midge Staverand Madeline Zung.

Asked whether the 117-acre tract for the proposed Tysons II shopping mall is for sale, as heard around town, attorney-investor Max Ammerman retorted "nothing could be farther from the truth." Ammerman and T.N. (Ted) Lerner are trustees for the owning group that has plans for another major shopping center opposite the original Tysons.

Relocation referral services are big in the house selling industry. Now there's Office Network, Inc., a nationwide real estate service dealing exclusively with information on business moves and expansion across the nation. Kornblatt Associates, with offices here and in Baltimore, has joined the network that is also represented by brokers in Atlanta, Cleveland, Dallas, Chicago, Denver, Houston, Los Angeles, New York City, Philadelphia, Pittsburgh, St. Louis and San Francisco.

Now residents of a new dwelling in Rossmoor Maryland, W.A. (Bill) Molster and spouse Gertrude recently sold their former residence at 4700 Berkeley Ter. NW for $170,000. Molster was a marketing specialist with the National Association of Home Builders for many years before retiring in 1977.

T.M. Kahn and other recently sold a small, multi-family property at 1020 Fairmount St. NW for $55,000 to Rosina and Harvey Marcus. And property transfer records also show that Johns Hopkins University sold a property at 2330 Massachusetts Ave. NW for $16,000 to the Association of American Universities.