I was limited by the processor and some existing ram which basically dictated my purchases to save money.
You’re completely right though, a more modern system would be similar in price and more capable.
I blew my budget on drives and a hot swap case. The rest is easy to upgrade when the time comes.
I purchased a case, SilverStone Technology CS382 8-Bay. Around $200-225.
Bought used parts off eBay:
Asus P8Z77-M LGA 1155 DDR3 SDRAM Desktop Motherboard $75
32GB DDR3 1333 $35
LSI 6Gbps SAS HBA 9200-81 IT Mode P20 $35
Nvidia Quadro P620 2GB GDDR5 4x mini DisplayPort $70
I have six 12tb drives (seagate exos), purchased refurb from serverpartdeals.com and had great luck with them and their support. I found that on Reddit data hoarder sub.
I run Truenas. 4 drives for primary. 2 drives for backup of the first 4. And I have a qnap 4 bay dumb raid box for a third backup with old drives I had. My paranoia but not related really to the nas.
Anyway it’s possible and I enjoy what I built. Also that case is loud, get a fan controller too.
I had an Intel s2600 with dual Xeon and 120 gigs of RAM. It seems like such a good idea to run that as a home server. However, the amount of power that it used because it was older was way too much.
I ended up hunting on eBay and found an old Asus motherboard, Intel chip, ram, and a pny Nvidia card.
I bought refurb hard drives from serverpartdeals and a new case from Amazon.
I recommend starting with a chassis you want and working backwards to help narrow your scope.
I know you wanted smaller but heres what I bought. SilverStone Technology CS382… https://www.amazon.com/dp/B0CKTYSZV9?ref=ppx_pop_mob_ap_share
Also, I run truenas scale with a bunch of apps. Ssd z1 for os. Ssd z1 for transcode and caches. And then 4 drive set for main storage and another 4 drive set for backup of the first set.
They are sata drives.
Seagate Exos X16. 6 of them refurb is still $800.
The case is hot swap with just an hba connection so I can let zfs do it’s thing.