NEW YORK CITY — Cignature Realty Associates has brokered the sale of a residential building located at 4300 Broadway in Upper Manhattan. Quantum Equities sold the property to Sugar Hill Capital Partners for $21.6 million. Built in 1955, the six-story, elevator-serviced building features 54 residential units and a 6,000-square-foot vacant retail space. The rent-regulated building features a mix of studios and one- and two-bedroom apartments. Lazer Sternhell and Peter Vanderpool of Cignature Realty Associates represented both parties in the off-market transaction.