Very coincidental with this post as I just started looking into creating a home server for the first time and decided that mini PCs were sufficient for my use case (originally was going with Small Form Factor).
Just bought a Dell Optiplex 7060 Micro from this website for <300AUD. I heard they were pretty decent for used PCs. The price difference isn't too far off from the USD equivalent here.
A$115 example, https://www.australiancomputertraders.com.au/hp-elitedesk-80...