Before the Hall County Board of Commissioners approved a $257,000 contract Thursday for the architectural design of a new Sheriff’s Office headquarters, questions emerged about whether due diligence had been given to looking at the possibility of renovating existing buildings instead, perhaps at a lower cost. The existing Sheriff’s Office headquarters at 610 Main St. in downtown Gainesville is the site of the old county jail. That facility was sold to the city of Gainesville in 2012; the Sheriff’s Office leases it from the city, with that lease set to expire in 2017.