The Reagan administration this week proposed a dozen ways to "privatize" the Federal National Mortgage Association, the nation's largest federally chartered secondary mortgage market institution.

The association, known as Fannie Mae, was created by Congress in 1938 to buy home loans from lenders as a way to provide more funds for mortgages, primarily for moderate-income Americans. Fannie Mae was rechartered in 1968 as a private corporation, but it retained a number of federal benefits that enable it to borrow at lower interest rates and operate at a lower capital/asset ratio than would otherwise be required.

The administration has been pushing for the removal of Fannie Mae's federal ties, saying the organization has accomplished the purposes for which it was given special status.

Removal of Fannie Mae's special status "could lead to increased competition in the {mortgage backed securities} market from private securities issuers and thus to a more efficient marekt," according to the Department of Housing and Urban Development report containing the proposals. These "policy options" range from a call for "full and immediate privatization" to maintaining the status quo.

David O. Maxwell, chairman and chief executive of Fannie Mae, said most of the suggestions, if carried out, would change the structure of the organization and weaken its value to moderate- and middle-income home buyers.

"Any fundamental changes in the current, very successful housing financing system require a great deal more analysis of the impact on home buyers and financial institutions as well as on Fannie Mae," Maxwell said.

IN THE BUSINESS... . The KMS Group Inc. and Constellation Properties Inc. have broken ground for Three Centre Park, a 57,000-square-foot office building in Columbia... . Long & Foster Realtors has opened five new sales offices in Maryland, including offices in Frederick, Calvert, Charles, Montgomery and Baltimore counties... . Franklin Property Co. has started construction of a 9,200-square-foot health and recreation center at the Holiday Inn at Dulles International Airport... . Real Estate Professional Realty Inc. of Annandale has purchased Nelson Realty Inc... . . The Oliver Carr Co. has finished construction of Republic Place, a 200,000-square-foot office building at the intersection of 18th and I streets in Northwest Washington.

PERSONNEL FILE... . John B. Buckner has been named vice president-controller for Mobil Land Development Corp.'s Virginia companies... . Nanci Porten James has been named vice president of residential acquisitions at the Milton Co... . Douglas P. Ayers, vice president of the C.J. Coakley Co. of Merrifield, has been elected to a second term as eastern regional vice president of the Ceilings & Interior Systems Construction Association... . Christopher Warner has been appointed president of 1st Washington Mortgage Corp... . William E. Carleton, senior vice president for John W. Galbreath & Co., has been elected president of the Building Owners and Managers Association International.