Boston-based senior housing developer Hebrew SeniorLife has leased 13,835 square feet of space for its executive offices at 300 First Ave. in Needham.

A 15,715-square-foot, single-story retail building at 714-724 Beacon St. in Newton has sold for $6.3 million.

A 21-unit apartment building at 333 & 333A Harvard St. in Cambridge has sold for $5.3 million.

Medical technology provider eWebHealth Inc. has signed a lease at 55 Walkers Brook Drive in Reading. The lease agreement includes 10,204 square feet of recently renovated, Class A office space.

Boston-based developer H.N. Gorin is set to acquire a Stoughton Class A office building, thanks in part to $5.85 million in financing from the Boston office of Holliday Fenoglio Fowler.