Depending on what you need, a NAS + Syncthing is much simpler than the linked article. Building a PC isn't hard, and keeps prices down. These days, a RPi 4+2 US

Depending on what you need, a NAS + Syncthing is much simpler than the linked article. Building a PC isn't hard, and keeps prices down. These days, a RPi 4+2 USB HDDs would run circles around the motherboard on my NAS. Syncthing is a great continuous backup solution. I use ~/NOTES as a scratchpad, and it updates automatically between my various computers. It gives you pretty granular control over shares, and I back up critical stuff to a cloud provider. That said, there's no calendar/email/notes. XigmaNAS is built on FreeBSD, and will happily run NextCloud or a photo gallery or whatever.