Getting insured for work that you haven’t done but intend to do is called a surety bond. The bonds called surety bonds are insurance policies that the contractor carries to protect his customers in case he can’t finish the job or the job is not done according to contract and the customer sues. Only those contractors who have the necessary qualifications can buy a surety bond.
The contractor must show assets and prior work completed as proof that he is a legitimate contractor who will finish the job. The contract that the contractor makes with a customer can be for say 30,000 dollars. His bond will not cost him 30,000 because if he has insurance, he is a reputable contractor with assets in property and equipment that far exceed the 30,000 dollar contract. If he doesn’t complete the job, his surety bond will pay and go after his assets to recoup.