Just as important as the scanner you choose is the file type and media format for your scanned documents. How will your aging in-laws access these files? Computer? If computer, then Mac or Windows? iPad? Spinning HDD or SSD? Duplicated for backup? Backed up in cloud? Will the documents be PDF files with OCR for text searches, plus maybe jpg (or tiff) files for photos and drawings?
Think for a few minutes - or days - about what your in-laws will do if you are not there to access their documents for them.
Fujitsu ScanSnap scanners should work well, but you shoud acquaint yourself with certain idiocyncracies. Search this forum for Fujitsu Scansnap and be prepared for hundreds of posts, many not complimentary of Fujitsu’s software changes from the older Scansnap Manager to the newer ScanSnap Home software. I have owned a ScanSnap 1500M for almost 10 years. In the macOS Sierra (or maybe Mojave, I forget) era Fujitsu’s software dropped support for older scanners (but not that old!) when switching to the 64-bit ScanSnap Home software. After much pushback from users, Fujitsu finally relented and updated ScanSnap Manager, which I still use with a current M1 Mac and macOS Monterey. ScanSnap Home came with license restrictions and cannot be used on simply any computer - it must be licensed to a particular computer (or maybe a limited number of computers, not sure of details or how you might transfer a license). Be sure that you understand the software licensing restrictions (onerous, in my opinion) before purchase. Just in the last two years I have used at least 6 to 7 “new” Mac computers, when you consider multiple replaced Motherboards on a 2019 Intel Mac, new macOS installs and recent switch to new M1 Mac computers (Mac Studio and M1 Max MacBook Pro). I truly don’t know how Fujitsu would handle all of these license “transfers” or how much of a hassle it would be if I used the new ScanSnap Home software with its license restrictions.
Try this older MPU forum link to get an idea of Fujitsu’s software issues in the recent past:
https://talk.macpowerusers.com/t/scansnap-s1500m-will-be-doa-on-mojave/7676/47?u=arthur
And this link, discussing early confusion with Fujitsu’s licensing restrictions:
https://talk.macpowerusers.com/t/new-scansnap-ixi500-october-12th/8333/29?u=arthur
DIsclaimer - these are old posts from 3-4 years ago. I don’t know the current status of Fujitsu’s software license restrictions. After a long period of turmoil, Fujitsu finally updated the older and unrestricted ScanSnap Manager software that I still use. Fujitsu has already announed that it will deprecate this software in the near future, so ScanSnap Home with its software license restrictions will be the only choice going forward.