I'm currently "up north"

, and while I'm cleaning out my attic for my TV move, I'd just like to get some recommended rules of thumb from you for what
CAN be stored in the attic. My attic never gets boiling hot in the summer, but that's not going to be the case in Florida.
So I'm wondering about the location (if space is available) "closet", "garage" or "attic" for the following:
- Luggage with plastic wheels (hard plastic or canvas suitcases)
- Christmas ornaments (wood, glass, plastic)
- Extra knicknacks (glass, wood)
- Papers (e.g. CC statements, old legal docs, tax returns)
I'm also guessing that cardboard boxes for storage are not recommended either? Rubbermaid or plastic file boxes are okay?
Many thanks in advance,
Kevin