Bro! I just came on this subreddit right now, to ask about the very same situation! In my case, I have well over 900 PDF documents, which a lot of them i transfered from my phone to computer. Then a good majority of them are full books, which I'ved OCR-processed and then turned into ebook format for Calibre web-server.
But the others are legal documents, tax documents, instruction manuals, research papers, etc.
I have Proxmox VE OS installed on two connected desktops in my apartment, I also have the ability to VPN into apartment router remotely and operate as if I where physically there.
The desktop app I want to run is AlfaBooks, they're like a better version of Calibre, only they cost like $40.00 for one time fee, which I am not opposed to. It also comes with their web server app, which acts like a Calibre Content Server.
However in the future, I may find othet desktop apps that I'd like to run on Proxmox without a VM in the middle.
Any ideas?
Since I have a Synology RT2600AC Router with VPN, I can VPN via my android OR Laptop into my home network when away.
I am wanting to install some kind of ebook manager on my Raspberry Pi 3, so that it syncs across my android and laptop, whenever I use them. And also stores the books there, without having me to download them onto my phone or laptop.