BOSTON — Locally based mortgage banking firm Fantini & Gorga has arranged a $13 million loan for the refinancing of The Berkeley Building, a historic office and retail property in Boston’s Back Bay area. The building was originally constructed in 1906. Wayne Clough and Colin Monahan of Fantini & Gorga arranged the 10-year, fixed-rate loan through Lincoln Financial Group. The sponsor, Boston-based A.W. Perry Inc., will use a portion of the proceeds to fund capital improvements.