Following is the page 1 from PC insurance quote, I think it does make a difference when your son is not at this address anymore. It seems to me the focus in on driver's history rather than the car itself. You can try the quote as anonymous, good luck!
Do any of the following statements apply to this quote?
A driver does not have prior auto insurance in Canada or the United States.
A driver has more than three (3) tickets in the past three (3) years (not including parking tickets).
A driver has more than three (3) claims in the past three (3) years.
A driver has more than two (2) accidents in the past six (6) years.
A driver's licence has been suspended in the last three (3) years.
A driver's insurance policy has been cancelled or refused in the last three (3) years.
A vehicle is more than 15 years old or is driven for commercial use.