AREA REAL ESTATE agents who are looking to fill up vacant office buildings might want to take note of the General Services Administration's current interests: leasing at least an additional 2 million square feet of new office space in the area over the next year -- most of it in the District.

Although the Reagan administration has insisted that it would try to shift government employes from leased space to government-owned buildings whenever possible, GSA has found itself in a bind to accommodate the consolidation of 11 agencies that currently are scattered around the city.

"Agencies want to consolidate their operations now that the budget cuts have reduced staffs and they find that they're scattered throughout the city. That's too hard for many agencies to manage," said GSA Regional Public Buildings Commissioner James G. Whitlock. "In the long run, consolidations become a cost-saving move."

In the chain reaction, many smaller blocks of space will be surrendered.

Currently, an estimated 8,370 government workers are in more than three dozen buildings scattered around Washington and into the suburbs. The plans GSA is working with call for 10,228 employes in 12 agencies to be given new offices in Washington and Maryland.

Virginia won't be totally left out, because a scheduled expansion of the Navy calls for a new 941-person unit to be housed in 115,000 square feet of space near Arlington's Crystal City. That leasing idea, however, hasn't been approved by Congress.

The biggest consolidation is also one that is the least likely to occur at the location GSA wants: On behalf of the Justice Department, GSA has been trying to buy or rent the 625,000 square feet of occupiable space in a new building at 1300 New York Ave. NW. Recently, however, the building's owners -- the Bank of Nova Scotia -- began negotiations with the Inter-American Development Bank for the entire property. If that deal goes through, GSA will be left out.

"That won't erase the need to relocate and consolidate many of the Justice functions," Whitlock said. "The question will be where."

Here's a rundown on GSA's other housing needs:

* The Environmental Protection Agency originally wanted to pull back 520 employes from Crystal Mall 2-3-4 in Arlington into its headquarters building at Waterside Mall (401 M St. SW). But an expansion of the staffing at the agency may add up to 1,200 new people, Whitlock said. As a result, GSA is looking to lease up to 120,000 additional square feet of space at the mall's twin towers. "We don't know if the Crystal City people will be moved or not," Whitlock said.

* The Bureau of Government Financial Operations, a segment of the Treasury Department, had sought a consolidation in downtown Washington, but GSA has decided -- with a little help from Congress -- to send the 1,200-person unit to the Center Two Building on East-West Highway in Hyattsville.

* The Federal Trade Commission wants to consolidate some of its employes into one building that can serve as an annex to its structure on the Federal Triangle. GSA has selected 400 Virginia Ave. SW, which is across town. GSA is in the final stages of negotiations with Smithy Braedon real estate firm over the new 120,000-square-foot block.

* Treasury's Bureau of the Public Debt is getting the boot from 1100 Vermont Ave. NW, and has decided that it wants to consolidate four units into one facility. GSA has selected 999 E St. NW for the 35,000-square-foot operation. Negotiations were completed recently with Jackson-Cross, the real estate agent for the owners -- the American Medical Association.

* Several units of the federal judiciary, including the Administrative Offices of the U.S. Courts, the U.S. Probation Office and the Federal Judicial Center, are scheduled to move into 555 4th St. NW, where GSA recently signed a new lease. The building is owned by the General Electric Equity Investment Corp. and leased to GSA through Coldwell Banker. GSA also is giving space in the 555 4th St. building to the U.S. Attorney's Office for the District of Columbia, which is leaving the U.S. Courthouse.

Next year, GSA will ask Congress for permission to find a new, 39,000-square-foot headquarters for the field office of the Secret Service. That office currently is cohabiting with the national headquarters unit -- which is expanding -- at 1800 G St. NW. GSA is willing to pay up to $35 a square foot

BLAIR HOUSE PLANS: Congress, in the closing days of the session, approved a $6.6 million renovation of the Blair-Lee House complex that is used to house visiting foreign heads of state. The renovation had been stalled for more than a year while Congress and the State Department bickered over the need for a special new "master bedroom" for visiting dignitaries. The new suite will be built on the back side of the complex, on a plaza that is surrounded by federal buildings and not visible from the street.

The design work will be completed in December. Construction will begin in March. Charline Keith, chief of staff to the Public Buildings Service, said other renovations will focus on historic preservation work, making the building fire-safe, replacing the electrical, plumbing and security systems and installing new heating and air conditioning .

NUMBERS SHUFFLE: The Jobs Bill of 1983 included a provision that allowed GSA to spend $125 million on repair and alterations work in federal office buildings during fiscal 1983 and 1984. The only catch: 75 percent of the funds -- or $94 million -- had to be spent in high-unemployment areas as determined by Labor Surplus Areas from the Labor Department.

GSA claims that 85 percent of the funds awarded were spent in areas of high unemployment, exceeding the congressional mandate.

But there's a little sleight of hand involved in reporting those numbers. Right off the top, GSA snatched about $20 million to pay for in-house design, management and inspection work on those projects, according to Wolfgang Zoellner, assistant commissioner for buildings management. Total amount available for the private sector: $105 million. GSA ended up spending only $89 million, or about 71 percent.

Did GSA fail to meet the congressional requirement?

"That's a very unfair interpretation," Zoellner said. "What should be said is that GSA did very well to do the best we could. There is a tradition, a legislative history, of using some of these funds for in-house back-up work. That's what we did."