Rentner Marine Services is the oldest family-owned and operated boatyard in Chicago, founded in 1941 by Paul E. Rentner II and his brother Conrad. Now in its second generation of family ownership, Rentner Marine has served Chicago's south side boating community from 13535 S. Forest Ave. in the Riverdale neighborhood for over 85 years. No other boatyard in Chicago can claim that kind of legacy, and it shows in everything they do. The Rentner family built this business on a simple premise: treat every boat like your own, be honest with customers, and stand behind your work. Decades later, that philosophy still drives every job that comes through their doors. Their 4.9-star rating across 27 Google reviews is not an accident — it is the product of generations of trust built one boat at a time. Customers describe them as attentive, straight-forward, and deeply knowledgeable. Many have been bringing their boats to Rentner for years, some since childhood.