I prefer using the metal cubes that you need to put together, they hug the walls. I drape a flat bed sheet from top to bottom to keep dust off, but this way the cotton fabric stash can breath. fabric tend to get that mold smell in plastic containers when its too hot too long, but 3 weeks dont seem too long. Here it gets over 100 so for me, i keep mines indoors on these metal cube shelving (costco/sams carrys them).