Duane was raised in the Independence area of Iowa . His family moved to Phoenix, Arizona in 1962 where his father started a successful real estate firm. After graduation from high school, Duane served in the U.S. Navy Seabees and upon returning from Vietnam in 1971, he and his wife Kay moved to the Branson Tri-Lakes area. With a construction background, Duane started developing subdivisions and established a real estate office, Gerken & Associates in 1975 with his wife, Kay.
Over the last 42 years, Duane has furthered his real estate knowledge by attaining the Graduate Realtor® Institute (GRI), Certified Real Estate Brokerage Manager (CRB), and Certified International Property Specialist (CIPS). He holds a diploma from the Missouri Auction School and serves as an Auctioneer Colonel for the firm's auctioneering division. He served as the 2001 National Association of Realtors® (NAR) Auction Committee Chair.
In 1985, Duane served as the President of the Tri-Lakes Board of Realtors® and received the Tri-Lakes Board of Realtors® Realtor® of the Year Award the following year. In 1998, he served as the President of the Missouri Association of Realtors® (MAR). He was honored to receive the MAR 2004 Realtor® of Year Award.
Missouri Governor, Mel Carnahan recognized MAR for creating a relationship with Japan and the State of Missouri through the Missouri Department of Economic Development. This MAR program was initiated by Duane in 1998, during his MAR Presidency. Duane led a trade mission to Japan comprised of Department of Economic Development staff and Missouri Realtors®.
Duane was one of the eight original charter broker-members that formed the first Multi-List System (MLS) for the Branson area.
A contributing member to the Branson community, Duane has served on several committees for the Branson Chamber of Commerce. He was instrumental in forming the Chamber's Legislative Affairs Committee, served as its chair for several years and is still an active member of the committee. He has continually served on the Tri-Lakes Board of Realtors® Legislative Committee.
Duane has attended the "Breakfast with the Legislators" in Jefferson City sponsored by the Springfield and Branson Chambers. He has served on the City of Branson’s Planning and Zoning, was Charter Treasurer for Christian Action Ministries (CAM) and Charter President of the Branson Tri-Lakes Lions Club. In addition, he has also served as a Liberty Bank Board member and on the Board of Directors for the Ozark River Heritage Foundation, a public/private foundation promoting the conservation and public enjoyment of all that Table Rock Lake has to offer.