The second part of the largest residential real-estate transaction in Erie County's history has closed.

A Cleveland-based hedge-fund trader, who remains anonymous, has closed on the second portion of the sprawling Russo family estate in Hamburg.

According to documents filed Thursday afternoon in the Erie County Clerk's office, the hedge-fund trader - through his or her Phantom Holdings One LLC affiliate - paid $3.3 million for the 15,500-square-foot complex, located at 6553 Boston State Road. The property had been owned by Greenacres Inc., according to public documents.

The deal is the companion to one that closed on Oct. 23, when Phantom Holdings One LLC paid $3 million for a neighboring five-bedroom house. Combined, the two represent the largest Erie County residential transaction ever involving a single-family estate.

Both properties were owned by members of the Russo family, who formerly owned Sorrento Cheese Co. but sold the South Buffalo food manufacturer to S.A. Perrier Co. several years ago.

The main house was built in 1985, the companion building seven years later.

The deal was jointly brokered by Susie Lenahan from M.J. Peterson Real Estate Corp. and Mary Zulawski from RealtyUSA.