Want to make sure if the contractor is really licensed to work on HVAC systems in your geographical area? Make sure they have a contractor license bond.
A contractor license bond (or contractor's bond) is a type of surety bond that guarantees to clients and the state that the contractor will do their job in accordance with state and municipal rules and regulations. If you're unclear on what these bonds are, learn how surety bond companies work. Contractor license bonds also protect against fraudulent practices.