The LDW charge will significantly raise the cost of your rental ($10-20 a day). Since you probably don't have a US based credit card with car rental coverage you might be better off getting an all-included European rate (not sure if Dollar has this, but Avis, Hertz, and co. ask for your country of residence) which will look more expensive but will have all coverage included. I'm not even sure if liability insurance is included on California rentals since the companies expect you to have liability coverage on your car insurance. Really much cheaper to get hold of a US based credit card somehow.