One thing to remember is to have oil separator and hoses made for winter.
I didn't remember to change those and the valve cover gasket and oil separator hose blew.
So ended up paying a bit more than if had changed the parts in time.

What comes to rusting, it's actually better if the car sits in freezing weather under roof, than if you drive it to warm garage after every short trip.
If you drive it to garage always, first it gets frozen outside and then warms up in the garage, and depending on how long it stays in garage it may get dry or just warms up to get wet before you take it out again and then it's basically all the time wet - good basis for rusting.