For this, you will have to contact your personal auto insurance company to know for sure whether the damage to your Pisa Airport rental car will be covered by your policy in full or not. Besides that, you can also check with your credit card company as they also offer coverage available to their customers. In case you are not covered by any of these, and the supplier is not offering CDW and THW with the deal, then it is advised that you buy it at the time of pickup.