Looking for storage advice

Hey guys, I have an absurd amount of warhammer and not enough space. I usually use the 6’x2’x1’ bookshelves from Walmart but don’t have room for anymore, I realized my wip models don’t need to be displayed and I was wondering if anyone has any suggestions for a more compact storage solution that takes up less space and can hold more smaller things like infantry. I’m planning on still putting big models and tanks and planes on the bookshelves but am looking for a way to mass store my infantry while still having access to paint it and hopefully not damage the models the way I would if I just threw them all in boxes. Any tips tricks or testimonials would be helpful. Thank you!