Ten housing developments with a total of 722 units have been given preliminary approval for federal rent subsidies that are needed for their sponsors to arrange financing for purchase or rehabitation, Mayor Walter E. Washington has announced.

Among the units approved for subsidies are 13 in the 63-unit Beecher lowrise apartments at 41st and Beecher Streets NW in Glover Park Beecher is one of the few moderate-rent developments west of Rock Creek Park. Its tenants are negotiating to buy the entire project for conversion in a cooperative.

Approval of the subsidies came from the U.S. Department of Housing and Urban Development. Under the subsidy program, tenants who qualify pay no more than 25 percent of their incomes for rent with the balance coming from HUD. Actual construction and rehabiltation work on the projects is months away. Sponsors still must obtain mortgage financing and final clearance from HUD. The District has started construction of rehabilitation of about 5000 units over the past three years, many under the same program.

In addition to the Beecher low-rise project, the HUD-approved developments include.

40 new garden apartment units on a city-owned site on Portner Place NW, just north of U Street between 14th and 15th Streets. It will be adjacent to a 171-unit high-rise building on the former site of the Dunbar Hotel.

80 new garden apartment units in Faircliff Plaza East, on the east side of 14th Street NW between Endid and Fairmont streets.

204 units in a high-rise building for the elderly at 8th and G streets NE.

52 rehabilitated garden apartment units in the LaSalle Apartments in the 5400 blocks of D and Drake streets SE.

93 rehabilitated units in the Carver Hall Apartments on Pitts Place SE.

37 rehabilitated units in the Garfield Hills Apartments, in the 2300 block of Hartford Street SE.

197 rehabilitated garden apartments and townhouse units in Atlantic Gardens in the 4000 block of Third Street SE and the 4000 block of H Street SE.

73 rehabilitated units in a walk-up-apartments development at 1715 15th St. NW.

23 units to be created by the rehabilitation and conversion of 11 large single-family homes in the vicinity of 15th and R and S streets NW.