SAN ANTONIO — Newmark has brokered the sale of Alamo Park, a 309-unit apartment community in northeast San Antonio. The property features one- and two-bedroom units with an average size of 658 square feet. Amenities include a pool, fitness center, volleyball court and outdoor grilling and dining areas. Jim Young, Matt Michelson and Chase Easley of Newmark represented the seller, Austin-based Achieve Investment Group, in the transaction. New York-based River Rock Capital purchased the asset for an undisclosed price and plans to implement a value-add program. Alamo Park was 94 percent occupied at the time of sale.