NEW YORK CITY — Locally based brokerage firm Brax Realty has negotiated the $52.5 million sale of a 65,000-square-foot office building located at 260 Fifth Ave. in between 28th and 29th streets in Manhattan’s NoMad District. The 12-story building was mostly vacant at the time of sale. Michael Ferrara of Brax Realty represented the seller in the transaction. Andrew Zang and Greg Albert of Savills represented the buyer. Both parties requested anonymity.