We are required by law to have liability insurance for our villa. Our provider ("Linea Directa", aka "Direct Line" in English) has a policy specially designed to meet all legal requirements for STRs here in the Balearic islands. Actually, it exceeds the base legal requirement as it also includes theft, fire, storm, earthquake, and [major] guest damage. It won't pay for petty damages though, such as ruined bedding.