G'day! I am looking to build a jellyfin server with the arrs through docker. Any advice is welcome.

I want to use quicksync and have expandable storage. An SSD cache would be nice too. Not fussed about back ups for this media as important files I have backed up 321. I can't afford a Synology Nas. I already have a bunch of SATA HDD's with media on them that I would like to utilise in this build.

I was thinking of some type of hard drive bay and an Optiplex/Thinkcentre?

Question is, how does the PC and the hard drive bay connect? Do I need any other hardware? Am I even on the right path here? Go easy on me, I'm new to this and on a budget. Thanking you all and here's to cutting the cord!