Contractors and Surety Bond

Your insurance, and the insurance that the building probably requires covers only damages to the building, possessions, and people that might occur during the renovation and are caused by the contractor and his agents.
A surety bond protects you against the contractor not completing the work as described in the contract (more accurately, provides some sort of cash payout if the contractor doesn't complete the work, so you can pay somebody else to complete the work).

Thanks Aaron. Is it common to have surety bond? My contractor does not offer that.

All you need is the insurance