Here is another option. On Ebay look for a used Lenovo ThinkServer TS -140 with 16gig of ECC ram and a quad core Xeon processor, and super quiet rubber-mounted fans all throughout the case. It will hold four 3.5” hd’s - five if you take the CD drive out. If you are patient you can find a clean one from a reputable seller in the low $200’s. Overall quality is a notch or two above your consumer grade machines.
Yet another option: I saw a refurbished ThinkServer a few days ago from a major online store in the low $400’s (newer model) that sported 8 drive bays with the same quality of processor and ram.