Monument and partners began building the tower last year and spent $50 million on the development. The property also features 19,000 sf of ground-level retail space, as well as a separately owned underground parking garage that accommodates nearly 500 vehicles. The offices are fully leased through 2013 to E*Trade affiliate E*Trade Bank, which relocated from Portland, OR to occupy the space. The joint venture began marketing the class A property over the summer through Cassidy & Pinkard at $55 million.

"We were always confident Ballston Tower would trade for a good number because the tenant, E*Trade, is doing well and the building is located in one of the best markets in Northern Virginia," Monument's Jeffrey T. Neal says in a statement. Speaking to GlobeSt.com, Monument's Michael Darby expounds on why the joint venture decided to put the property on the market. "Monument, as well as our investment partners, Apollo and Prudential, is a group that creates value by holding on to a property until the point in time that maximizes returns--and this was that point in time," he says. "The market in Washington is very buoyant for the sale of Class A assets inside the beltway."