David R. Horn, the owner of a commercial real estate firm, died of a pulmonary condition Jan. 29 at the University of Maryland St. Joseph Hospital. The Mays Chapel resident was 89.

Born in Philadelphia, he was the son of Paul Horn, a Sun Oil manager, and his wife, Helen, a homemaker. He earned a degree at the University of Pennsylvania.

Mr. Horn joined the Army and was stationed in Germany. While in the military, he met his future wife, Grete “Marge” Greller, who worked for the U.S. government as a telephone supervisor and interpreter during the Nuremberg War Trials.

He later joined the Sun Oil Co. and worked in sales. In 1960 he moved to Baltimore as a district sales manager. In 1978 he switched careers and went into real estate and appraisal work and attended the Johns Hopkins University to study courses in that field.

Mr. Horn was qualified as a real estate and zoning expert before the Circuit Courts of Baltimore, Anne Arundel and Harford counties.

He was also a senior vice president for office, retail and industrial leasing and marketing at MacKenzie and Associates. He later founded his own commercial leasing business, David Horn and Associates, in Ruxton.

He served three terms on the Maryland Attorney Grievance Committee. He also did work for Baltimore County on zoning matters pertaining to oil businesses.

He was a member of the Country Club of Maryland and Royal Woods Country Club in Naples, Fla., where he had a second home. He followed the Orioles and Ravens and played tennis and golf.

A celebration of his life will be held at 1 p.m. Thursday at Towson United Methodist Church, 501 Hampton Lane, where he was a member.

Survivors include his wife of 65 years, a former bank teller trainer; two daughters, Lynda Schultz of Cockeysville and Gail McCurdy of Lutherville; a brother, Paul Horn of Arizona; four grandchildren; and two great-granddaughters.

—Jacques Kelly