Auto insurance does not cover all accidents under the sky. Your regular car insurance does not cover certain accidents such as theft, vandalism, damage caused by falling trees, hail, floods, fires, etc. To get coverage for such accidents, you must purchase the optional comprehensive and collision coverage. But these are additional insurances, and most people who drive old cars do not buy them to save on costs. For example, if a car has a value of $ 1000 or less than ten times the premium, it makes no sense to buy the optional coverages. But if you drive a relatively new car and want to get coverage for all types of damage, you must buy both comprehensive and collision coverage.