President Carter yesterday said any federal aid for Chrysler, Corp. should be at a "minimum" with "maximum security for any loans or guarantees."

At a town meeting in Burlington, Iowa, during the president's Mississippi riverboat trip, Carter said the troubled auto company's request for government assistance "very cautiously."

The White House has turned down a Chrysler plea for a $1 billion cash advance on tax credits but indicated it might support loan guarantees of up to $750 million. Carter stressed yesterday that the guarantees would not come without strings.

"Chrysler must change," Carter declared, adding for instance that any aid package will require the nation's No. 3 automaker to "reconstitute their management."

The president's remarks came a day after Treasury Secretary G. William Miller was quoted in an interview with the Wall Street Journal saying it is possible Chrysler will put together a rescue plan strong enough to eliminate the need for federal assistance.

Though most auto industry observers doubt Chrysler will be able to save itself alone -- and may in fact end up needing several times more than it has asked for -- Miller's remark was an indication is to keep its involvement in the Chrysler crisis tentative and as limited as possible.

Treasury officials, while monitoring Chrysler's recent moves carefully, have taken a wait-and-see attitude, pending receipt of a formal and detailed proposal from Chrysler that will show how the automaker expects to turn profitable again. The plan is scheduled to be submitted to Miller shortly after Labor Day.

In recent weeks, Chrysler has adopted a host of cost-cutting measures and has laid off roughly a fifth of its work force. To spark sluggish car sales and reduce swollen inventories of cars and trucks, the company has also announced substantial dealer discounts and $400 customer rebates on most automotive models.

In a further effort to raise cash, Chrysler yesterday announced it has signed an agreement to sell for an undisclosed sum its real estate s subsidiary, Chrysler Realty Corp., to a real estate investment firm in Wichita, Kansas.

The subsidiary currently controls 775 Chrysler dealerships, or about 15 percent of the automaker's total number of U.S. dealers, according to a corporate statement. The dealerships account for about 80 percent of the subsidiary's holdings. The rest is represented in a diverse collection of other properties. All told, Chrysler's current investment in Chrysler's Realty is valued at nearly $200 million, according to the company.

Chrysler Realty purchases, finances and develops land generally in major markets for Chrysler dealerships, which in most cases are leased to individual dealers. Under the terms of the agreement, Chrysler will sell all of the shares of its subsidiary to ABKO Realty Inc., a real estate firm set up as a partnership between George Ablah and Koch Industries, both of Wichita.

Ablah is a real estate dealer and shopping center developer with extensive holdings around the country. He is chairman and chief executive of the partnership.

Koch Industries is a privately-held petroleum production and management firm headed by Charles Koch, who Town and Country magazine last year ranked among the 22 richest people in America. Reticent and reclusive, the 42-year-old Koch reportedly has amassed a personal fortune estimated at between $400 and $600 million

His company controls about 30 subsidiaries which cover a broad section of the energy business, from chemicals to pollution control devices. The company was started by his father, Fred, in 1925 as a refinery construction company. Two brothers, William and David, help manage the company. A third brother, Frederick, is an actor in New York City.

In its announcement, Chrysler said that Chrysler Realty will operate under a new name but will keep the same management structure. Edwin n. Homer said he would remain president of the realty firm and assured dealers the company would continue to help them in their real estate operations.