As a collector of tarot and oracle decks, storage is always a problem. I still don't have the ideal solution. I wonder if I ever will. Part of my problem is not just keeping them somewhere but with hundreds of decks, how do I arrange them? By publisher? By theme? By type? Alphabetically?
Right now, I have ones that I like and use more often in a nice cabinet purchased for the sole purpose of storing my cards. Others, that I don't use often or have mostly for reference as well as the foreign editions of my projects, are in the <shudder> basement in Rubbermaid (tm) containers.
I keep decks in their original packaging if possible. If not, I put them into bags, either purchased,