You need a title and a bill of sale the title should be signed over to you when you buy the car and theme bill of sale says how much you bought the car for and date from the seller
Title signed over to you, bill of sale, drivers license, social security card if you never registered a car in VA, Name of insurance company
To add to Alem's response, you will recieve your title, new plates, and a temporary registration on the spot. You will then be asked to come back for your permanent registration after passing inspection. I was able to get the temporary registration early enough to get an inspection and get back to the DMV in time to get the permanent registration all in the same day. If you plan ahead you can knock it all out so you don't have to come back and wait again.
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