Washington's new downtown YWCA, scheduled to be open this summer at 624 9th St. NW, will demonstrate how a community-service association can take advantage of the strong office-leasing market in the redeveloping old commercial district.

In addition to providing a headquarters for areawide YWCA activities, the new free-standing building will have facilities for in-city members on four floors, including a large pool, physical activity rooms, meeting and craft rooms and a basketball court. The first-floor pool will be open to men and women.

The top four floors of the eight-story building designed by the Chloethiel Smith firm will have windows facing the Martin Luther King Library courtyard on its north side and will be occupied by private tenants (mostly associations) able to pay leasing rates in the $16-to-$19 range. Other nearby YWCA neighbors include the National Museum of American Art and the National Portrait Gallery.

The John Akridge Co., which develops downtown office buildings, worked with YWCA officials in developing and leasing the new structure that is set off by a 35-foot-high entrance foyer inside a glass skin. The Akridge firm bought the former YWCA building at 17th and K NW and now is building a new office building there.

Currently, the YWCA is embarked on a 75th anniversary capital campaign to pay the difference between the $9 million development cost of the new building and the $7 million sale price of its former headquarters. Esther Peterson is heading the fund campaign that includes several Washingtonians active in varied sectors of real estate -- Flaxie M. Pinkett, Julia Walsh, Foster Shannon, Thomas A. Owen and Joseph Riley.

Elsewhere on the commercial realty front:

The Oliver T. Carr firm has acquired the Mazor furniture store property at 905-07 7th St. and 630 Massachusetts Ave. NW for $2.6 million.

The National Association of Retired Federal Employees bought the building at 1531 New Hampshire Ave. NW for $850,000 from Mr. and Mrs. C.C. Alpert.

The American Council on Education leased 48,000 square feet of warehouse space at 641 S. Pickett St. in Northern Virginia through Coldwell Banker. The 10-year-lease involves more than $1.7 million.

Arthur Rubloff & Co. negotiated a relocation for Market Facts, a marketing and research firm, to 1611 N. Kent St. in Arlington.

Barnes, Morris & Pardoe arranged the sale of a commercial office building at 3255 K St. NW to Temporaries Inc. for about $1.6 million. The two-story building in Georgetown's Papermill complex was sold by Columbine Inc.

Government Services Administration has renewed a lease for the Navy Department to continue using 52,000 square feet at 4228 Wisconsin Ave. NW at an annual rate of $13 a foot with normal services. C. Duke Brannock represented the building ownership in negotiating the $3 million lease.

James and Ted Pedas, owners of the Circle Theater chain, bought the Lank Woodwork Co. property at First and K streets SE from the P-Z Partnership, with Coldwell Banker the broker. A renovation of the 36,000-square-foot industrial complex is planned.

The Compressed Gas Association will move its national headquarters from New York City to One Crystal Gateway, a new building in Crystal City, according to John H. Brody of the Charles E. Smith Companies, the developer of Crystal City.