I use an Asus 86RU running Asus-Merlin. It ticks all of your boxes.

I’m not sure how I would do that. What sort of application would I use? Postgres doesn’t have a webui to log in through. So not sure how else I could test it.

Followed that guide. Got redis and postgresql14 installed. When installing immich I get an error in the log that says "error:password authentication failed for user “postgres”. I’ve trirled every combination of changing password, no passwords whatever. It never works.

Yes, but the Readme says it requires postgresql14 or 15 external. I don’t see how to set that up. I usually go through the app store that is included in unraid. Usually there are good guides but I don’t see one for this.

I use Mail in a Box running on a digital Ocean instance for like 12 USD a month.

Look for spaceinvaderone on YT. He has great tutorials for almost everything. One note of caution, the Unraid UI has evolved, so some things ma look different.

I also run Unraid with Plex, Sonarr, Radarr, Prowlarr and Overseer running as dockers. Its a great system.