Two women, one 87 and the other 35, were the realty brokers involved in the spectacular transaction that resulted in the 40-acre Archbold estate, being leased for 99 years - for $1 million a year.

Realtor Frances Powell Hill, who opened her own firm in 1936, represented the Archbold family, owner of the estate on Reservoir Road NW. Hill, a friend of Anne Archbold, who died in 1968 at age 94, has specialized in selling large estates over the years. Anne Pallie, who opened her own brokerage firm here in 1973, has specialized in commercial property, leasing and sales of large tracts in West Virginia. She represented Hillandale Development Corp. Inc., which is headed by Clinton W. Murchison Jr. of Dallas.

Pallie pointed out that the deal includes an agreement for the sale of the property at the seller's option and also includes outright purchase of the mansion. The Archbold Investment Co. has a two-year lease on the mansion, plus a one-year lease on the gatehouse that is part of the property. Hill and Pallie have worked together on other deals. "But this is the largest for both of us. Although we have separate companies, we will continue to work closely with each other," Pallie added.

H. Harland Crowell, who has operated his own real estate brokerage firm in Northern Virginia since 1955, has sold a substantial interest in the business to Richard Purvis, owner of Dominion Realty. Crowell, who began selling real estate in 1951, said he has turned to home building for change of pace. "My first four houses in the 3200 block of N. Kenmore Street, off Roberts Lane, in north Arlington, are nearly completed," he said. "And all are sold."

In a recent edition of the AIA Journal, Washington writer Don Winter points out that President Carter designed a small health clinic built in Plain, Ga., in 1959. The article quotes builder Ralph Wiggins, who also built the Carter home in Plains, as saying that Carter made a "rough sketch" of the layout of the clinic that is nearly square. As the writer pointed out, the clinic (now being slightly enlarged and refurbished) is "aesthetically quite similar to President Carter's second effort, the so-called tree house for Amy he caused to be erected on the White House ground. (A platform set on four corner poles, it is near, not in a tree.)

If the history of mortgage interest rates shakes you tree, be reminded that the maximum FHA-VA rate was 4 1/2 percent until Dec. 2, 1956. Now the rate is 9 percent and reports on the street indicate it may be raised soon to 9 1/4. The FHA-VA maximum was 9 1/2 percent in the latter part of 1974, a period when mortgage money was both expensive and in short supply. Then the ceiling was lowered to 8 percent in early 1975. The last time the FHA-VA ceiling was under 8 percent was in 1973 and the last time it was under 7 per cent in early 1969. And the last time it was under 6 percent was in 1966. From 1956 through 1968, the maximum rate ranged between 5 and 6 percent. Sweet nostalgia.