The horizontal vs vertical storage thing is interesting. I've often wondered what the rationale is with the difference, and it seems that it's cultural to a large extent.
One thing that wasn't covered, that sometimes matters for non-institutional collections, is that cardboard is thicker than plastic, and can add quite a lot to the number of boxes required for a given collection. Polyester or polypropylene sleeves (open at the top, and stored vertically, i.e. to allow gas exchange) can be as cheap and sometimes are a better option, at ~0.08 mm vs ~0.5 mm.
One thing that wasn't covered, that sometimes matters for non-institutional collections, is that cardboard is thicker than plastic, and can add quite a lot to the number of boxes required for a given collection. Polyester or polypropylene sleeves (open at the top, and stored vertically, i.e. to allow gas exchange) can be as cheap and sometimes are a better option, at ~0.08 mm vs ~0.5 mm.