The onetime headquarters of Hampden Savings Bank at 1665 Main St. in downtown Springfield is once again for sale. The 1,800-square-foot space was built by the bank, now part of Berkshire Bank, 99 years ago for $100,000 -- nearly $2 million in today's money. It is on the National Register of Historic Places. Most recently it was the law office of Barry Kaufman, and before that it was the office of him and his father, Kaufman & Kaufman. The building has housed law offices since 1965, Barry Kaufman said.