The insurance company is only going to pay you so much. By getting 3 bids you are actually helping the insurance company save money and doing yourself an injustice. The insurance company is not going to give you the difference of the savings if you find a lower bid. The roofer that bid the lower amount is going to have to cut costs somewhere, where do you think that cost will come from? It is going to come from the quality of your roof. Find the roofing company that is going to work for you and give you the best quality and roof you should have and pay to have through your homeowners insurance.