What is the cheapest way to get car insurance for a 17 year old girl on a shared car?

I'm going to assume that you still live at home with your parents and in HS. You would be added to your Parents policy and be listed as a licensed driver. Are you an Honor Roll student? There can be a discount for being on the Honor Roll and you may be required to provide proof. The vehicle that you get can have an impact on the premium an inexpensive car vs. a High-Performance or newer vehicle can make a difference. Narrow your choices down and then ask your Agent to quote each of them on your policy for you. Cheap Insurance, however is not always the way to go. In fact the more I think about it you've given me a thought to take back to the office. Not that you are going to be a risky driver, but you will be inexperienced. Have your agent share and explain with your parents the level of coverage they have. Then have them ask the Agent how much it would cost for extra coverage. So if as an example they have BI (Bodily Injury) limits of 100/300 find out how much it is to increase to 250/500 or 500 CSL (Combined Single Limit). In some cases the cost to increase the coverage is so minimum that a person is foolish not to increase. Stacking Limits may also be an option with Multiple vhcls. on the policy. If your parents aren't familiar with Insurance they may be really impressed with your sharing this info.