According to a representative of the Virginia Department of Motor Vehicles there is not an age restriction regarding buying or registering and title a car in your name so a 16 year old can be an owner of a vehicle but when they register the vehicle they will need to have the minimum Virginia Liability insurance on the vehicle. This Liability insurance needs to remain on the vehicle while the vehicle has valid license plates.
It is up to an insurance company whether they will write a policy for a minor, such as a 16 year old. Generally an insurance carrier will require those under the age of 18 (and thus still a minor) to have a parent or guardian sign with them on their insurance documents since they are legal documents.
The VA DMV did not state that a parent would need to be on the title or registration of a minor however you may want to contact them directly to make sure you do not need a parent or guardian to sign with you on this paperwork.
If you are buying a car from a dealership it is likely that the dealer will also require a parent or guardian to sign or co-sign with you because normally when you sign on contracts as a minor the paperwork may not be binding unless an adult of this nature signs with you.
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