An affordable housing complex in Sterling sold for $27.15 million, commercial real estate investment firm Greysteel announced last week.Located at 46565 Harry Byrd Hwy., the 150-unit Cascades Village Senior Apartments sold to Irvine, California-based Avanath Capital Management LLC, which focuses on acquiring existing affordable housing properties. Developed in 2001, the apartment complex is age-restricted (55 years and up).