I did some storage for my set I just came across. The link below is cheap for smaller squads and units, but I definitely wanted something bigger and better. So I went to my local hobby store and bought a few medium and a deeper one for dragons and such from the company ArtBin. They are great, but I wish they interlocked and stacked. I also just grabbed some CD sleeves for my cards. Seem to be working great.
cheap:
https://www.amazon.com/gp/product/B089LN5J14/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1
better:
https://www.amazon.com/stores/ArtBin/page/3746E89E-8B04-4D10-970A-DE33DD09065F?ref_=ast_bln
Cd Sleeves:
https://www.amazon.com/gp/product/B00S05R5QY/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1