An undisclosed buyer has acquired, for $13 million, the 28,350-square-foot development site at 159-18 Northern Boulevard, located between 159th and 160th streets in Flushing’s Murray Hill section. The site is currently occupied by a two-story commercial building, a former branch of Flushing Bank, Crain’s reported. If the existing structure is demolished, the site could accommodate a maximum 56,700 square feet of development. Nearly 38,273 square feet could be used as residential space, whereas up to 28,350 square feet could be commercial space. Any amount, up to 56,700 square feet, could be used as community facility space. Plans for the site have not been disclosed.