Former Redskin John Nisby has announced that Development Group Ltd., based in the District, will develop a $1.5 million, six-unit apartment project in Culpeper, Va. Nisby said that financing for the moderate-income project will be handled through the Farmers Home Administration. Thomas Harkins Inc. will be the general contractor. Other principals in the Development Group are Lonnie Sanders, also a former Redskin, and Harold L. Kramer and Joseph W. Maguire Jr.

The District of Columbia Builders Association will hold a reception Tuesday at the National Housing Center, where invited guests will include District government officials and members of the Senate and House District Committees.

Virginia Homeowners Inc. has announced a series of free seminars on real estate topics. Reservations may be made by calling 451-7040.

Better Homes Realty Inc. is distributing free booklets dealing with home financing. Copies are available by writing Better Homes, 6045 Wilson Blvd., Arlington 22205. The brochure was prepared for the Homes for Living Network, with which Better Homes if affiliated.

The Northern Virignia Builders Association has announced plans to train 30 disadvantaged persons in carpentry, heating and air conditioning. The training program is open to residents of Fairfax and Loudoun counties. Information is available by calling 893-6800. Applicants may also apply directly to an office of the Virginia Employment Commission.

The Maryland Association of Realtors will hold its annual convention June 21-23 in Ocean City. More than 1,000 are expected to attend.