At the beginning I can start with the laptop battery. Later I can remove it and use an external battery/power bank to keep it running. Once I set it up I feel I’ll have more time troubleshooting this too. Thanks.

I’m going to attach some used hard disks and ssds, I have many spare ones. I wanted to set up a RAID2 or 3, so even if some disks dies it’s not the end of the world.