A seminar to aid prospective purchasers of condominium dwellings will be held next Saturday at the Alexandria campus of Northern Virginia Community College. Attorney Francis Gindhart is the instructor for the four-hour session, which begins at 9 a.m. Information is available by calling 323-4240 or 323-4280.

Seminars on home buying without a down payment are being scheduled by Househop, an firm headed by Patricia Press. Information is available at 399-5284.

A 2.9-acre commercial land site at Diagonal Road and Reinekers Lane, near the Metro station on King Street in Alexandria, has been sold to the Oliver T. Carr Co. by the Pisner and Eig family limited partnership. The Carr firm plans to build an office and retail building on the site. Barnes, Morris & Pardoe represented both parties in the transaction.

Financing of $16.5 million has been arranged for a multiuse building planned for 2201 Wisconsin Ave. NW by a partnership whose general partners are Melvin Lenkin, Edward Jay Lenkin and Robert Melnick, the Walker & Dunlop mortgage banking firm announced. The building will include office space and 44 cooperative apartments.

Citicorp Homeowners Inc. recently opened an office in Annandale. It will finance mortgages of more than $150,000 and serve executives involved in interstate transfers. Beth Nielsen is manager of the office, which is at 7535 Little River Turnpike.

The Red Carpet real estate franchise system recently honored the affliated Market Homes in Vienna and Sentry Realty in Manassas for high volume of sales. Top sales associates were Jean Rousek, Lewis Good and Edward Shore.