After redeveloping a Fort Point warehouse into a 120-room extended-stay hotel, Norwich Partners has sold the Residence Inn Downtown/Seaport for $77 million to a South Shore real estate firm.

Claremont Cos. of Bridgewater acquired the real estate for $64 million and paid an additional $13 million for ongoing business operations, Norwich Partners’ CEO David Leatherwood said.

Located at 370 Congress St., the building was originally constructed in 1901 by Boston Wharf Co. Norwich Partners redeveloped the vacant structure into a loft-style hotel with exposed brick walls, 12-foot ceilings, large windows and kitchens. The hotel opened in 2013 and was named “best custom project” in 2014 by Marriott International. The property includes ground-floor retail tenants Caffe Nero and sweetgreen.

HFF’s Denny Meikleham, Alan Suzuki and Matthew Enright represented the seller.

Claremont Cos. owns more than 20 commercial properties including the 174-room Hilton Garden Inn Boston Brookline, which broke ground in July at 700 Brookline Ave.