Validus Group has signed a deal with one of its existing tenants to take over the entirety of a building in Sabal Park. Electrostim Medical Services, Inc. has signed a lease for an additional 11,825 square feet at 3504 Cragmont Drive, making it the sole occupant of the 58,000 square-foot building. EMSI, which specializes in home electrical stimulation units and accessories for management of pain and physical rehabilitation, was already in the building…