I can give you an example to explain how your refund amount is determined
What happens if my name has changed since I registered the plates, can I still get a refund?
If your name had changed and you are looking for a refund, bring the plates with you to the DMV office when surrendering. Yu must request a transfer receipt and not a refund receipt. You then send these to the address that you'll find on the Request for Refund MV-215 form
How is my refund actually determined?