I use BCW Shoeboxes to store almost everything. The player cards are all in their own box sorted by faction, then 0 XP or 1+ XP, then card type using a top loader with a custom printout as a divider between them. Each campaign is in a Return To... box if it is out or a shoebox if it isn't. Each scenario in the campaign is stored in a 35 count hinged deck box and has a custom label on the front with the campaign symbol and scenario number. Encounter sets are stored in the same deck boxes but 15 count instead with the name and symbol of the encounter set on a label. Having those little boxes makes set up and tear down before and after each scenario fairly quick.

I created a google drive to store the labels and low ink campaign logs that I use.