Not only are they water resistant so you can easily store them in a garage or outhouse, but they also have lightweight and strong lids, making stacking super easy. They come in a range of colors too - transparent is ideal so you can see what is inside them easily, but if you do not have much space for storage and will need to keep them in your bedroom say, a coloured option may be better. You will certainly be able to find something to tie in with your decor. If this is your idea, purchase a taller box and double it up as a bedside table for instance. Any spills are easy to wipe off and by incorporating your storage and furniture you can easily maximise your space.
https://www.info-plastic.com/product/child-safety-seat-mold/

The costs of such storage boxes are pretty low considering the lifetime of use you will achieve out of them. You should easily be able to choose a storage box for $15. Size and brand will obviously affect the cost but to get the best value for money stick with a good make. You can also buy tailor made boxes if you want a special shape to fit into your closet say.