Leasha, I don't think your parents would need comprehensive? Even if they just had 3rd party, you might still be able to get some sort of reduction in price?? Though I could be totally wrong here too.

Most insurance companies also offer a reduction in your premium if you do a skilled drivers course. I know AAMI reduce your premium by 10% if you do one of those courses. You can even check out when they have a course next available (Sunday 21st March @ Brissie TAFE, Gateway Campus )

Do you have contents insurance? If you do, you could ring your insurer and ask if they do car insurance. You might get a little discount for mulitple policies.