Bait is proven way more effective. Kill the queen/s & the colony/ies. Extermination only kills the local pawns.
Look for Exterra or Sentricon Bait System Contractors.

For new construction, the most effective infestation prevention system is RETRICULATION, a laid network of subfloor perforated piping. This allows periodic termicide application that can cover the entire footprint of the structure.

