Best bet is to pick up an old HP Z620 of find someone who is upgrading their old Xeon homelab. Generally its a choice of cheap, quiet, energy efficient and you can only pick two of these options.
Someday I'll have a proper closet but right now my rack is under the kitchen and my wife complains when the servers get above about 60 dB.
I actually built my desktop as a near silent PC with the goal of it becoming my NAS when I upgrade but I didn’t understand the implications of running ZFS without ECC at the time.
So while I'd certainly sleep sounder with ECC on it, it's not a complete horror show like someone likes to portray it as.
I have had one stick give me issues over the last 10 years but that is out of probably 20 sticks.