The leasing operations also provided General Electric with tax shelters from accelerated depreciation on equipment that GE developed that were then leased by the credit corporation.

Analysts said the unit might be worth as much as $500 million if it were sold, while the leasing operation could fetch as much as $350 million.

Mr. Penske, the company's chairman, attracted notice in business circles by turning around the leasing operations that his company acquired from the Hertz Corporation.

G.E. said eight of its 12 businesses had increased earnings, led by a 19 percent increase at GE Capital, which runs one of the world's biggest commercial jet leasing operations.

Mr. Fisher was for many years in charge of the company's leasing operations.

Arthur H. Lerner, now vice chairman of Newmark & Company, ran the commercial leasing operation of Helmsley-Spear for almost 30 years.

The sale, which also includes Douglas Elliman's store leasing and office sales and its leasing operations, is expected to close in June.

Early in the 1980's, the company ran into financial troubles centered on an ill-fated leasing operation that it was eventually forced to liquidate.

The company earned a 15.4 percent return on equity in the second quarter; it does not break out the return for its leasing operation.

Although Durst usually handles the leasing operations for its office buildings internally, it has signed up with the Ellis organization to handle the leasing for the CyberCenter.