The rental price is always inclusive of a full insurance cover. This includes, in addition to civil liability and legal assistance, a full omnium cover (own damage, theft, fire, glass-break, overflowing game, ...).
If you have any damage or an accident during your trip, you can get support 24/24, 7/7 from the call center anywhere in Europe. ViaVie has taken out a fleet insurance with AG Insurance which you can rely on excellent damage statistics.