You are required to insure your project to 100% of the final value of rebuilding. Remember this is not the market value of the project, but the replacement cost in building. This value will not include the value of the land. As you are doing the building or you have a contract with a builder, who will be building the project this should be an easy number to come up with. Remember the cost is not high for this product and you are best estimating the costs on the high side. This leaves you some room in your number if costs go up.