In case there are any changes that need to be made in the policy such as address change or any particular changes regarding the automobile or its usage, it could be done by an endorsement by the insurance provider. You need to submit a letter to your insurance provider along with the proof of the changes so that you could obtain the endorsement. There are few endorsements that might charge an extra premium from you.
Auto insurance is financial protection, and not just for the investment you made when you bought your car. After a really serious accident, bills for damage and injuries can easily reach into hundreds of thousands of dollars. If you happen to cause such a wreck, the victims could sue you. In the worst case scenario, assets such as your savings and home could be seized.