Mostly what others have said, with the addition of car cover and garaged (actually, heated garage). Regarding the rodent concern, I have a cat in my garage...found this works better than particlewave's "incantation and line of salt", unless you consider a cat an "evil spirit"

. Also, or so I've been told, used cat litter is an effective deterrent against mice...I'd be happy to send someone a few hundred pounds should they wish to cover shipping.
Before anyone actually considers filling their car up with used cat litter, I would highly advise against doing so...I don't purchase scented litter.