Hi Dini, yep, I fell down that rabbit hole when I discovered I could do hot foil with my laminator! I have some rolls, some A4 size sheets, lots of smaller sheets. I've got an A4 sized paper storage box I keep most in. I do keep the majority of the offcuts & smaller pieces in a smaller box, as I've found them useful for when I want a multiple of colours on my project, like these.
I also have a few of the wallets that some Sizzix/Tim Holtz dies come in, and they are useful for storing bits in too, as it keeps them flat.