Reddit mentions of (20) 8.5" x 14" Document Topload Holders - Rigid Plastic Sleeves - BCW Brand

I’d recommend buying a fireproof and waterproof safe, which I bought for my artifacts at a hardware store. It’s never big enough, but at least it suffices for the most valuable items.

And just as a temporary measure, since you’ll handle some items over and over while organizing the collection, you can individually ziplock some items, to reduce skin oils. It sure beats wearing gloves. This way is also good so that you can jot notes on post-its and slap them on the ziplocks. Later when everything is sorted, you can remove the photos & docs from the ziplocks to put in a more dignified storage.

For some items, I’m having customized floating frames made, which is expensive, but should be worth it. Framing them isn’t for display purposes per se, but just to preserve. I’m still unsure about which to use - glass or acrylic. I don’t know if ink will leach into either one.

And for wrinkled documents that you’d normally put between two books to flatten out, I recommend these plastic sleeves instead. They’re great - not for putting anything in them, but between them. These are heavy rigid plastic sheets, and I lay a wrinkled document between two sheets. Since they’re transparent, you can see where the remaining wrinkles are, and reach in with a toothpick to straighten them out.
(20) 8.5" x 14" Document Topload Holders - Rigid Plastic Sleeves - BCW Brand https://www.amazon.com/dp/B00KAENV2A/ref=cm_sw_r_cp_api_i_8.EuDb2F1RTWV

I have a lot of documents relevant non-relatives, so I scan them and upload them to findagrave.com so that descendants of these strangers don’t have to pay anything to view them.
issuu.com may be good if your documents are several pages long, like a book.

Lastly, if you buy binder sleeves, make sure they don’t have glaring branding printed on them like “Office Depot” for instance.