It's a buyers market, but who's buying?

House prices and mortgage rates, which surged upward following the Federal Reserve's credit-tightening measures Oct. 6, now have begun to drop perceptibly because of customer resistance.

"High home prices inevitably mean large mortgage amounts," said William B. O'Connell, executive vice president of the U.S. League of Savings Associations. "Many potential buyers consequently are discovering that their monthly mortgage payments may strain household budgets -- and are postponing purchases."

Loan closings nationwide last December were estimated at $5 billion, off 39 percent from the previous year and 32 percent from the previous month.

In the Washington area, the average price of a new house dipped from $105,900 in September to $100,800 in December. Resale houses, which sold for an average of $108,600 around Labor Day, sold for an average of $82,000 over Christmas, according to the Federal Home Loan Bank Board, although figures can vary widely from month to month.

Across the country during the same period, prices for new homes continued to climb, from an average of $75,500 in September to $79,200 in December, while the average price for an existing residence dropped from $67,000 to $64,300.

Due to the relatively small volume of sales, the agency cautions against drawing too many conclusions. However, prices apparently have been affected far more adversely in the metropolitan area than in the nation as a whole. Consequently the wide spread that formerly existed between average prices here and throughout the nation has narrowed.

Mortgage rates -- which hit their peak of about 14 percent in many parts of the country during November -- generally have come down a percentage point since then. Lenders have been obliged to cut rates for competitive reasons, even though they have comparatively little money to lend. Their profit margins are already razor-thin and many say they are hurting.

Banks and S&Ls in Los Angeles and San Francisco last week lowered their rates by an average of 1/4 percent, to 12 3/4, with the lowest at 12 1/2. tIn Cleveland, the best rate for a loan with a 5 percent down payment remained at 13 percent, but a buyer willing to put down 30 percent could get a 12 1/4 loan -- and pay two points. (A point is 1 percent of a loan and is immediate additional income for the lender. It is payable at settlement. Multiple points often are divided between buyer and seller.)

Closer to home, Baltimore Federal Savings & Loan Association this week cut 1/2 percent from its mortgage rate, reducing the charge on a loan with a 20 percent down payment to 12 1/4 plus two points.

According to Walter Preston, publisher of a weekly survey called Builder, Bankers & Realtors, interest rates charged by Maryland lenders making loans in greater Washington reached their zenith Nov. 26. A conventional loan with a 5 percent down payment bore an average rate of 14.27 percent, while one with 25 percent down was going on average for 13.04 percent. p

That month also witnessed the greatest shortage of funds in the current economic cycle. Sixty percent of the 309 lenders surveyed weren't making loans, 12 percent limited loans to old customers and another a fourth of them would make loans only with down payments of up to 50 percent.

Preston's survey of last week showed the average loan with 5 percent down was pegged at 13.63 percent; with 10 percent down, 13.52 percent; with 20 percent down; 13.20 percent, and with 25 percent down, 12.72 percent. Nearly half (48 percent) of the 305 institutions reporting last week still weren't lending.

Peeke & Associates, which questioned 247 lenders last week in the District, suburban Maryland and Northern Virginia, reported a higher percentage of open lending windows in each.

As for interest, of those District institutions currently lending, 37 percent listed rates between 13 percent and 14 percent, while 29 percent were charging between 12 percent and 13 percent for a 30-year loan of $75,000 maximum with 5 percent down. The highest rate, 13 1/2 percent plus two points, was posted at Friendship Savings & Loan Association in Maryland, and the lowest at Inter-City Mortgage Corp., which charged 12 percent and three points. Other active lenders require customers to call for rates.

With a 25 percent down payment, the highest rate, 13 1/2 plus one point, was charged by United National Bank of Washington, but with a maximum loan of up to $200,000. The lowest, again, was Inter-City Mortgage, at 11 3/4 percent with three points, up to $93,750 maximum.

The steepest terms were offered by Union First: 13 3/4 percent interest plus two points with a one-third down payment and a maximum of $100,000. Only three lenders listed FHA-VA-backed mortgages as available at 11 1/2 percent and on payment of three or four points.

In Maryland; 41 percent of the lenders were charging between 13 percent and 14 percent, while 27 percent were charging between 12 percent and 13 percent on their highest loan-to-value ration. With a 5 percent down payment, the top fee of 14 percent plus two points was set by James W. Rouse & Co. and Loyola Federal Savings and Loan Association, both with a maximum of $75,000. The low of 11 1/2 percent plus three points was charged by Guardian Mortgage and Investment Corp.

By putting down 25 percent of the price, a buyer still get the best deal from Guardian at 11 1/2 percent with a $93,750 limit, and the stiffest from John Hanson Savings and Loan Association: 14 1/2 percent with a $100,000 ceiling. Only two lenders were interested in making FHA-VA loans with four or five points.

In Virginia, one-third of the lenders were charging between 13 percent and 14 percent, while 38 percent set a rate of between 12 and 13 percent. The high of 14 percent plus two points was shared by VNB Mortgage Corp. and Rouse & Co. The low of 11 1/2 percent plus three points was registered by Guardian Mortgage and Investment Corp.

Where 25 percent down was required, the high of 14 percent plus two points and a $100,000 ceiling was set by John Hanson S&L; the low of 11 1/2 percent plus three points and a maximum of $93,750 was charged by Guardian. Two lenders listed FHA-VA loans with four points.

The future doesn't look too bright for either availability of funds or interest rates, judging by figures released this week. The U.S. League reported that last month, commitments to customers to make them loans within 60 to 90 days fell to their lowest monthly level in nearly three years.

The $15 billion in commitments was 15 percent below November's level. And the Federal National Mortgage Associaiton, which buys loans on the secondary market from financial institutions, expects interest rates four months from now to be 13.291 percent for conventional loans and 13.105 percent for FHA-VA loans.

The figures for four-month commitments have risen during the last three auctions and are the highest since last Nov. 26 for conventional and since Oct. 29 for government-backed loans.