New Canaan, CT An affiliate of Besen Partners, LLC, a New York-based full-service real estate advisory firm, has leased 258 Elm St. to Bankwell Financial Group. Bankwell signed a 10-year lease for the entirety of the 30,000 s/f office building, which will serve as the group’s headquarters. Its award-winning subsidiary, Bankwell Bank, is considered one of the state’s leading banking institutions, with 12 branches throughout Fairfield and New Haven counties.