I live in Portland and have a slide-in truck camper on my property. I use it for camping of course, but it is also part of my earthquake preparation plan. It is solar powered but also has a built-in propane generator. It is fully self-contained with all the comforts of home including fresh water storage, a galley with oven, stove, freezer and fridge. A bathroom plus a hot shower, comfortable bed, large pantry, closet, etc.
It sits on a 3500 diesel truck that can go just about anywhere.
I know this solution is not practical for everyone. But it is always fully fueled, fully stocked and offers considerable peace of mind. If you have been on the fence about buying an RV, think of it from this angle.