I went with the Dell Optiplex 7050, which at $160 was overkill for the server, but it's replaced my main computer also, a huge desktop tower. It's about 50% faster than my desktop, but much nicer. It looked brand new inside and out, but there are lots of these on Amazon from various providers, so I can't vouch for all of them. But a friend who saw mine bought one, and he's happy, although his didn't have an unneeded addition with bluetooth and wireless N. I didn't need it either, but it's there.

Mine came with 16 GB RAM, and a cheap 256 MB SSD, both of which work fine. The drive is super easy to take out (one thumb screw on the case, and no other screws). The RAM is a single memory stick. Came with Windows 10, and I shrunk that partition and added Linux Mint as the main system, which works perfectly.

It's got two audio outputs on the front, one a cell-phone style with mic jack, and one regular mini phone plug. It could easily hook up to a stereo system, and has video outputs that could go to a TV if desired, but can be used as is with another Plexamp device to control it.

I use it with external USB 3 drives; it has about half a dozen USB 3 jacks, including one type-C and B on the front.

Let me know if you have any other questions. Oh, here's the link, but from a different vendor: https://smile.amazon.com/dp/B08GCX4JKJ?psc=1&ref=ppx_yo2ov_dt_b_product_details

Mine was from VR Laptops.