You do not mention your age and that may have an impact on the answer. However, given the information you have provided, one solution would be for you to buy your brother's and sister's share of the car (you would own it outright), get a loan yourself to cover the amount remaining due on the car, and purchase your own auto insurance. Another would be for each of you to retain your 1/3 ownership and for you to purchase a better insurance policy that would cover the entire value of the car as well as adequate coverage for any harm or damage you cause to another person or property if you do have an accident. As long as they own part of the car (and the accompanying liability if anything happens), they have right to say how the car is used.
Answered on Jun 29th, 2015 at 4:52 PM