A congressional appropriations subcommittee this week denounced efforts by the Department of Housing and Urban Development to cut back spending on housing for the poor by 70 percent.

"Most of the agencies who come before us used the 4.3 percent" level of spending cuts required early this year to comply with the Gramm-Rudman-Hollings budget deficit-reduction law, said Rep. Edward P. Boland (D-Mass.), chairman of the HUD and independent agencies subcommittee of the House Appropriations Committee. In contrast, Boland said the subcommittee found HUD's deep cuts "distressing."

"There ought to be a better way of meeting the deficit-reduction problems the department has" than making massive reductions in housing assistance funds, Boland said.

Last February, HUD made 4.3 percent cuts in all its programs to meet the deficit-reduction law's first deadline, but then, in its fiscal 1987 budget request announced a few days later, proposed to rescind $5.1 billion appropriated for fiscal 1986, nearly all of it for subsidized-housing programs. HUD also asked to defer spending another $2.3 billion in fiscal 1986 subsidized-housing appropriations.

In its proposal for fiscal 1987, HUD requested only $5.5 billion for its entire budget, one-third of the 1986 appropriation, and wants to spend little of it on subsidized-housing programs.

HUD Secretary Samuel R. Pierce Jr., appearing before the subcommittee during hearings on the department's budget, said HUD's proposed fiscal 1987 budget "reflects the present reality that the federal deficit threatens healthy economic growth." When asked whether he considered 70 percent cuts in housing programs fair, Pierce replied, "This is something Congress should look at and judge . . . what they believe is fair."

HUD's requests for rescission of 1986 appropriations died when Congress failed to approve them within 45 days after they were submitted. Deferrals can take effect unless Congress disapproves them. A supplemental appropriations bill approved by the House Appropriations Committee contains provisions killing all of the proposed deferrals and ending the president's authority to defer spending money voted by Congress.

If the provision terminating the president's authority remains in the bill after it has passed the House and the Senate, President Reagan is almost certain to veto it, several Capitol Hill sources said. The bill may be considered by the House by the end of next week.

Plans to limit housing assistance to 50,000 vouchers, which low-income families can use for a portion of their rent, also drew fire from subcommittee members. HUD is putting "all its eggs in one basket" with the voucher program, Boland said, which "will be very costly" and could evolve into an entitlement program such as food stamps "that will be practically impossible to stop."

The first batches of vouchers, good for only five years, will begin expiring at about the same time as tens of thousands of Section 8 rental assistance certificates, which last 15 years, presenting the federal government with a bill that could run as high as $75 billion to renew them, Boland said.

Changes in guidelines for appraising a home that would reflect its market value more accurately will be put into effect on July 1, the two major institutions in the secondary mortgage market said this week.

The Federal Home Loan Mortgage Corp., known as Freddie Mac, and the Federal National Mortgage Association, or Fannie Mae, will require that all loans they purchase be based on appraisals made using the new market-value definition.

The new rules will ensure that appraisals reflect only the market value of homes, by eliminating the value of sales concessions or creative financing used to attract buyers, particularly in times of high interest rates and flagging sales. Appraisals that include the value of financing concessions are misleading because they inflate the property's true worth.

Under the change, market value is defined as the "most probable price" of a property if it is sold, rather than its current definition as the "highest price which a property will bring."

The two corporations buy home mortgages from lenders, thus providing funds for more loans, and sell the mortgages or securities backed by them on the secondary market. Fannie Mae also holds some mortgages in its own portfolio. Together, Fannie Mae and Freddie Mac buy about half of all conventional loans sold.

IN THE BUSINESS . . . The RELO National Housing Report says that the Washington area, at $143,600, has the fourth-highest average home prices in the country, behind Los Angeles ($152,700), San Francisco ($151,600) and New York ($147,300) . . . The Virginia Association of Realtors reports that home sales were up 30 percent in the state in the first three months of the year over last year, from 15,882 to 20,691. The Northern Virginia Board of Realtors says that sales were up 25 percent in its region for the first quarter, from 5,304 to 6,624 . . . The Maryland Association of Condominium Owners (MACO) and the Maryland Attorney General's and Secretary of State's offices are sponsoring a day-long seminar next Saturday on condominium ownership. It runs from 9 a.m. to 4 p.m. at the Sheraton Silver Spring, and the registration fee is $10, which includes lunch. For more information, call MACO at 428-1942 . . . Evans Co. has started selling 67 condominiums at 1099 22nd St. NW ranging in price from $135,000 to $750,000 . . . National Development Mid-Atlantic Inc. has started construction on a $13 million, 139-unit apartment project known as Ballston Place, between Vermont and North Utah streets in Arlington . . . Jack Dogget, Tom Goodwin and JoAnna Pillis have formed Evergreen Development Associates Inc., a real estate consulting and development firm in Vienna . . . Edw. R. Carr Cos. has bought the Landmark Professional Building at 5249 Duke St. in Alexandria for $5.2 million and the Packer Park East apartment complex in south Philadelphia for $8.3 million. Carr Properties has started construction of Old Bridge Estates, 363 town houses and 255 detached homes in Prince William County . . . Donohoe Construction Co. has begun construction on a $24 million office and condominium project at 2121 Wisconsin Ave. NW . . . Ken Murphy & Associates, a new home-marketing firm, said March was the best month in the firm's three-year history, with 214 sales for a volume of $32.7 million . . . Mount Vernon Realty said it sold $262.3 million worth of homes last month . . . The home-building firm of Porten Sullivan Corp. said it sold 261 homes in the first quarter of the year worth $33 million . . . The Montgomery County Housing Opportunities Commission has about 125 loans available for moderate-income first-time home buyers at 8 7/8 percent interest for 30 years.