It may or may not be appropriate and coverage may not be available or affordable. Consider some unique problems. AUTO Cell phones are not covered unless scheduled on your Auto policy. If not factory installed, this may not be covered unless scheduled. Anyone you allow to drive your vehicle, in effect, will be using your Auto insurance.
Insurance follows the vehicle.
CD's are not covered by your Auto Insurance. They are covered under your homeowners or renters insurance. If you rent a vehicle, your personal auto policy may not carry over to the rented vehicle. You may have to purchase insurance through the rental service. If you own land which is vacant, you should extend liability to this property.