The Joshua Coffer Gunnell Building has won the seventh annual commercial appearance awards sponsored by Fairfax City and its Chamber of Commerce. The 21,000-square-foot building at the corner of Sager Avenue and University Drive was built by Hersand Builders, Inc. of Burke . . . Merrill Lynch/Chris Coile, Inc. is establishing a realty scholarship fund for area students attending the University of Maryland and the University of Virginia. Recipients will be chosen on the basis of financial need, scholastic achievement and desire to attend college. Application forms may be obtained for local Merrill Lynch Realty offices. Periodic benefits will be held to aid the fund; the first is scheduled for Nov. 17 at the University of Maryland Founder's Room . . . Frank Hardy Inc, Realtors, of Charlottesville, working with Sotheby Parke Bernet, announced that the 264-acre Hilton farm in the Somerset area of Orange County, Va., has been sold, for $1,875,000. The sellers: Mr. and Mrs. Roy Johnson of Bridgeport, Conn. The buyer: Hilton Farm, Inc., which plans to continue raising angus cattle and to step up the equestrian operation. Construction of an indoor arena is planned . . . On now at the D.C. Armory is the sixth annual Design for Living show sponsored by Regardie's Magazine. The show, which goes through tomorrow, features more than 300 exhibitors of home products, ranging from heating to bathrooms to gardens and beyond.