Buying insurance adds a lot to the daily cost of a rental -- Avis, for example, has a loss/damage waiver of $29, plus $3 for personal accident insurance, $1.25 for theft coverage, and $12 for additional liability insurance, all charged daily -- but having too little can be a disaster if there's an accident. If you own a car, first check your existing auto insurance
policy for rental car coverage. Many credit card companies also provide some insurance automatically if the card is used to pay for the rental -- but see how much is covered and when. Some policies provide only reimbursements, meaning the renter is on the hook to pay for damages upfront and only gets reimbursed later, when the insurance company has reviewed the claim.