The cost for insurance will be determined by the location of the vehicle as well as the type of vehicle.

Auto insurance typically covers the car, not the driver. So, if you have insurance on your vehicle, but you drive another vehicle that doesn't have insurance, you are not protected by your policy if you have an accident in that other vehicle.

However, if you have insurance on your vehicle, and you lend it to a driver (from another household) who does not have his or her own insurance, they will be covered by your policy while they are driving your car.

Your personal auto insurance will be secondary to the insurance of the vehicle that you are driving (assuming you do not own it and it is not a business vehicle). If you get involved in a car accident while you are operating a vehicle that is -not- yours, then the insurance of that vehicle has to pay first, and if that insurance is not enough (or is not there) then your insurance will kick in. Notice that if you get pulled over by police they will ask you to show proof of insurance on the vehicle (not your insurance.) The law requires all vehicles to be insured, not individuals.

Many auto insurance companies offer commercial vehicle insurance. For example, Geico offers commercial vehicle insurance. You can talk to your local agents too.

If you don't own a vehicle, or have no intention of driving, you do not have to maintain auto insurance.