A little more than a year ago, an imaginative Washington real estate agent who goes only by the name of Basheyba had a bright idea. She telephoned then-Vice President Nelson House and suggested that Rockefeller sell his 25-acre estate in the exclusive Foxhall Road section of Northwest Washington.

"I knew that I could sell the property," said Basheyba, a warm, energetic frequently wears a following, floor-length canary-yellow cape. "From the beginning I knew I would. You feel things. God puts us on earth to do certain things. Mine is to put people together with property."

Thus began the saga of the Rockefeller estate that has now embroiled some of Washington's most prominent and wealthy citizens in an uncommon effort to preserve the rolling, heavily wooded estate from what they see as the possible ravages of a major Washington developer, Rozarsky and Kay Construction Co., that plans to build more than 100 homes there ranging in price from $300,000 to $400,000.

"This is what I wouold call the hypocrisy of snobbery," said the firm's Alan Kay, of the citizen's complaints. Kay, 43, is a navy dresser and an intense man whose carefully groomed gray-brown hair comes close to hiding his ears. "What we're going to build there will be every bit as nice as what's already there. If I didn't buy it then someone else would. Once the decision was made by Rockefeller (to sell), that was it."

The story of the sale of the Rockefeller property, pieced together from interviews with Basbeyba. Kay and others, paints a fascinating picture of big wheeling and dealing in the real estate industry in this town and of a new era when the great estates that once dominated so much of northwest Washington are breaking up in the face of what once was considered suburban-style development.

The property was on the market for nearly a year at and $8.25 million asking price before Rozansky and kay nailed down the $5.5 million contract that they now hold. During that time, according to Basheyba and other real estate sources, scores of developers and others viewed the property and decided the price was too high or the conditions too risky to attempt anything there.

Despite the citizen protests and the threat of legal action to stop the project. Kay said his firm, of which he is half owner with Allen Rozansky, plans to go ahead and break ground in the spring after final settlement with Rockfeller takes place. Kay appears least two strong factors in his favor.

First, while a great deal has been made of the power and prestige of those opposing the development, Rozansky and Kay itself is a rich privately held company for which the Rockefeller project is, aside from its publicity aspects, somewhat run-of-the-mill. Development costs, including the price of the land, are planned at about $24 million for this project.

Kay said the company built 13,000 apartment units in the Washington area during the 1960s and early 1970s including Marina Towers in Alexandria, Yorktowne Square in Fairfax and Forest Lake in Greenbelt. It still owns 5,000 of the apartments and has now turned to town houses, condominiums and office buildings with four projects totaling $85 million now under way and six more projects beside the Rockefeller one and worth $60 million planned for starts early next year.

Second, the Washington Post has learned from impeccable sources that the contract contains special clauses quite helpful to Kay and that appear to reflect Rockefeller's eagerness to sell the property after it was a long time on the market without a sale.

For example, settlement cannot take place until Rozansky and Kay either resell 10 acres of the property for at least $2.5 million or waive their right to do so - a provision that gives the firm an option if they have difficulty obtaining financing. It was learned, however, that the firm doesn't plan to sell off these 10 acres since it has tentatively obtained a dequate bank financing.

The contract also contains a clause saying that, prior to settlement with Rozansky and Kay, which must take place by early March of next year. Rockefeller may entertain other offers. However, Rozansky and Kay still retain the final word, since they can still purchase the land for $5.5 million even in the face of a higher offer merely by setting a quick settlement date.

If the deal eventually does not go through for some reason such as effective citizen opposition. Rozansky and Kay stand to lose $50,000 at most under the contract, it was learned.

Basheyba who works for Town & Country Properties Inc. said that after phoning Rockefeller's office in late 1976 about selling the estate, she immediately received a return call from Bill Yates of William J. Yates, Inc., the Rockefeller family's long, time real estate agents in Westchester County, N.Y.

Yates came to Washington the following weekend, she said, and the two spent several days touring northwest Washington so that yates could get a feel for the area that would enable him to set a price on the Rockfeller estate.

The area includes some of the most beautiful and expensive estates in Washington, as well as less expensive houses set side by side on quarter-acre lots. The larger residences include those of former Geico chairman David Lloyd Kreeger, former ambassader to Denmark and the Philippines William McCormick Blair, and Gwendolyn D. Cafritz, widow of the late developer Morris Cafritz.

The estate was put up for sale early in December for $8.25 million. "Then I took as many people to that property as I could," said Basheyba. "I know I brought 29 developers, and there were others: embassies and individuals. Probably everybody in Washington other real estate agencies) was showing it."

Developers shied from the property, she said, because they didn't know what the market would be for the kind of high-priced homes that would have to be built there, because the price was high and only a very large developer could handle such a project, and because they feared citizen opposition.

Mary Ann Case of Town & Country, Basheyba's supervisor, added that, "It's a rough piece of ground," difficult to develop because of the steep terrain.

Edmond Howar of Howar Development Corp., one firm that was shown the land and decided against buying it, explained: "It's a big (price) and you're talking about a five-year development program and that's a lot of carrying charges. You're talking 10 per cent for five years, plus developments costs. You don't find many developers who can handle it, and also how many $400,000 homes cant the market absorb?"

But Kay, on the other hand, said he could see several advantages in buying the property. For one thing, it was already zoned for the kind of houses he wanted to build there and he felt that, despite expected citizen protest, city officials could not object too strongly to a project that will increase the city's tax base by tens of millions of dollars.

In addition, because the property had been on the market so long, he was able to come in successfully with a low offer.

"I met Alan Kay for the first time at the property," said Basheyba, who had obtained his name from Mary Ann Case, an old friend of Kay, and taken him there soon after the property went up for sale. "I knew the moment I saw him that that man wanted to buy the property. I also knew that many things had to happen before he was going to."

Kay didn't buy then because the price was too high. But the persistent Basheyba called him again this August, nearly a year later. "I said, Alan, it's time now for you to buy the Rockefeller property. Do not miss the most incredible opportunity of your life." He said, I'm going to buy it. Bring the papers over tonight. Call the Rockefeller office. Tell them we're going 'o draw up a contract.'"

Why did Rockefeller, with all his millions, sell the property?

"Look, he's had that house 33 years," explained Hugh Morrow, a Rockfeller spokesman. He actually used it between 1940 and 1945. Then he used it for a couple of years during the Eisenhower adminstration, from 1953 to 1955. . . The house base been staffed and maintained and run at considerable cost for 38 years for use 10 per cent of the time. Times change. He's no longer Vice President, no longer in politics. . . It just reaches the point where it doesn't make sense any more to hang onto it."

Kay said his engineers are studying the property's possibilities. He said he will soon pick landscape and building architects. He said the approximately 100 houses will be built of brick in the federal style.

"It's going to be a very exclusive group of homes with an entrance gate and guards, that kind of thing," said Kay. He said some of the houses would have "elevators and things like that. Some will be three stories. . . All will have two-car off-street parking. We're now looking into amenities tennis courts and swimming pools for the area residents. .. There will be four, five, six bathrooms. For $300,000 you have to give 'em something.

On the other hard, Kay said, finally decisions on what exactly will be built, and how, have not been made.

He said it was "ludicrous" for area residents to be so upset when "we don't know what's going to go there. Yet they're up in arms." He also said that many of the protests live in houses near the estate on quarter-acre lots - the same size lots that he is planning to build on.

Kay said that he is "looking for a purchaser" for the Rockefeller mansion itself and the few acres surrounding it, but he indicated that if no purchaser is found then the house might be torn down.

The protesting citizens have complained that Rozansky and Kay plans to level the ground and buildoze down trees. Kay said he plans to leave many of the old trees and preserve the contours of the land when possible. He said leaving the original trees may cost $1,000 more per house in the construction but will add five times that much to the sale price.

"A developer can't just go in and build junk houses." said Kay. "He must consider the market and the area. . . The banks have quite a biot that the development be an asset and profitable."