The Reagan administration begins its long-awaited and troubled land sales program today by offering 82 pieces of "unneeded" federal property, ranging from seven acres of housing on Bolling Air Force Base here to 65 modular buildings in the town of Camp Lonely on the north slope of Alaska.

Originally unveiled with fanfare as a way to raise $17 billion in five years for the federal government and help reduce budget deficits, the program is opening inauspiciously. It is under fire from both Democrats and Republicans, and has met resistance from administration bureaucrats.

The administration so far has designated 778 properties that could be sold, but only 82 have worked their way through a maze of federal property laws and regulations to be put on sale today by the General Services Administration.

This summer, the White House urged federal agencies to surrender 307 unneeded but potentially high-value properties to add to 471 surplus tracts already in the GSA program. But only 51 of those properties have been turned over to GSA for disposal. Of those, the U.S. Army Corps of Engineers supplied 37, all unneeded lakefront tracts.

Joshua A. Muss, executive director of the federal Property Review Board shepherding the program for the White House, said yesterday he is not discouraged by what he termed procedural delays.

"The problem is just time," Muss said, "You have to believe when the federal government owns 744 million acres of property that somewhere there is $5 billion of surplus property that can be sold in the next 24 months. That certainly doesn't sound like an unreasonable figure."

The 82 parcels going on sale today, covering 5,904 acres in 31 states, include:

* The Sullivan Hotel, a federal office building in Brooklyn.

* 22 industrial buildings on the U.S. Date and Citrus Station in Indio, Calif.

* 2.2 acres of unimproved land on Old Telegraph Road in Prince William County, Va., obtained by a court order from a man who had defrauded the government.

* Portions of 34 military installations, including missile sites in Miami and California and 40 buildings on a U.S. Air Force radar station in San Luis Obispo County, Calif.

All parcels must be screened, sometimes for up to a year, for possible use by other government agencies or for the public benefit before being sold.

For the first time, GSA will rely on commercial real estate agents to handle about half of the sales.

The administration aims to raise $1 billion from this year's property sales and another $16 billion in the next four years, when the program will expand to include public lands under control of the Interior and Agriculture departments. But some federal bureaucrats and the Congressional Budget Office have criticized the target as unrealistic.

Interior officials, originally told to raise $4.8 billion, predicted they could generate about half that amount by selling 4.4 million acres of "unneeded" public lands. Some of them question whether the land would sell for that much in today's depressed real estate market.

The program also faces legal hurdles. Under present federal law, money from the property sales could not be used to help balance the budget, but must be used for park acquisition. Several congressional leaders, including Rep. John F. Seiberling (D-Ohio), have promised to fight any change in that law.

The GSA official in charge of the sales program said yesterday that the main obstacle so far is the delay by other agencies in making property available for sale. Many federal bureaucrats are "reluctant to release federal properties that are being underutilized because there may be some future need for them," said GSA's Carroll Jones.

"That's the hardest nut to crack," said Jones, commissioner of GSA's Federal Property Resources Service. "If the land is not turned over to us, we can't sell it."

One property that hasn't reached GSA yet is a 17-acre stretch of Waikiki Beach that is now part of Fort DeRussey in Hawaii. Defense Secretary Caspar W. Weinberger personally promised to put the beachfront land up for sale, and a department spokesman said yesterday he could not explain the delay.

Many military lands marked for sale have been held up because they must be submitted first to the House and Senate Armed Services Committees. In the rush to adjourn last week, the committees deferred any ruling on property sales until the lame-duck session.

Muss, a Dallas attorney who started his job this week, said with a newcomer's optimism that he expects these obstacles to be cleared by the end of November. By then, he said most of the 307 tracts selected by the White House board should then be in GSA's hands.

The new director also said he is not discouraged by warnings from several bureaucrats that the sales target is too ambitious, or that it would require the government to sell public lands or forests it should retain.

If the agencies do not turn over enough property to meet the targets, Muss said he may direct them to come up with more. "That's one of the options," he said. "That's certainly one of the options."