I can't remember who posted this earlier this summer, but her daughter would copy the thermal type receipts and keep them together since the thermal receipts tend to fade.
That is an excellent tip.
I didn't like my binder that I tried for the manuals and bought a portable plastic file box, which I keep in my closet out of sight unless needed. I do want to get a second one because its gotten rather stuffed.
For my legal documents I was keeping them in the bottom of a file drawer that I kept extra supplies in, no files in there though.