A 30-unit apartment building located in Somerville’s Union Square has been picked up by the Mount Vernon Company in a $12.1 million deal. Webster Court was built in 1988 at 25 Webster Ave., and consists of 30 units in a single five-story, elevatored building. The community offers 30 market-rate apartments, 87 of which are two-bedroom homes. There are 40 off-street parking spaces, with half of them covered space. CBRE/NE’s multi-housing experts Simon Butler and Biria St. John represented the seller, Danvers Land Associates, and procured the buyer. “We are very pleased to have facilitated this transaction on behalf of the seller,” said CBRE/NE’s Biria St. John. “Webster Court represents a fantastic urban infill apartment property in one of Boston’s hottest submarkets where Mount Vernon can execute their value-add strategy again by making improvements to the apartments and common areas.”