Hi Jake and welcome! We’re always glad to help out where we can and I’m glad you came here for our help! 
Sometimes it is really hard to change a parents mind, especially when the animal has been destructive but you can rabbit-proof areas, or even better, set up an x-pen as Baxter’s home and he won’t be out and about, chewing cords, wires or setting up camp under your couch or bed. However, something I am thinking that you could do now though (while he is in the garage) is litterbox train Baxter to show how well-behaved he is (if he isn’t already). When you let him run around, does he have a litterbox available? Rabbits do go to the bathroom a lot because they have to keep their GI tract constantly moving, and also why they should have a constant supply of hay avaialble – which could also be an issue with your parents because hay is messy. Is there a way to ask them what exactly bothers them about having him indoors and if you could fix the things that bother them so much about him being indoors if they would give him another chance? Then, when you have more specifics we can give you all the tips and resources available and help you work with your parents.
How about I give you some links to information on why rabbits make great indoor pets read up on them, and then you if have any ideas of what you want to do or how you are thinking about approaching it, you can run it by us and we’ll help you try to convince your parents?
http://www.rabbit.org/care/living-with-a-house-rabbit.html
http://www.vrra.org/rabbits101.htm
Here are a few bonus resources for house rabbits:
http://www.rabbit.org/
This is the link to the home page of the Vancouver Rabbit Rescue – http://www.vrra.org/