Unfortunately, we live in a society that loves to litigate. If your passengers get injured in an accident, they can still sue you - no matter how much coverage you have. Also, unfortunately, your liability is to protect the party in the OTHER vehicle. It will not apply to the passengers in your vehicle. Also, your personal auto policy will not cover a claim resulting from an accident while you are transporting people. You will need to purchase some kind of business policy that will cover delivery of people. And, with that policy, you will want to purchase as much insurance as you can afford to protect your passengers.