Well here's my pick...
HP TP01-2337c Desktop with AMD Ryzen 5 5600G 8GB 1TB DVD, $400 refurbed from ebay. Thanks for the Ryzen pointers, looks to be a screamer compared to my current machine.
I know I'm locked into a proprietary case/mobo/PSU but I don't really upgrade anything anymore, just run them into the ground.
I was like that for a while.
I did get an ASUS ROG B350 board, Ryzen 5 2600 and a AMD Radeon R9 380 based card from my son last year in exchange for buying his plane ticket to Seattle for my oldest daughter's wedding.
Since ASUS finally released an upgraded BIOS, I did find a Ryzen 5 5600x yesterday for $160 and upgraded. Well that and his old Radeon RX 580 graphics card.
The graphics is totally overkill as I don't game. But I know both cards work, so I can sell another one.
I also was able to sell his old 780Ti based card. Insane money for a 3GB card that came out in 2013. That more than paid for the "new" CPU.
He did say anything he left I could get rid of. I've been funding my upgrades from the proceeds of selling his old kit.
The only new items in the PC I'm using are the PS, the DIMMs and the M.2 boot device. Spinning storage came from my previous machine, the case from FB marketplace.
The plane ticket was a companion fare on Alaska, BOGO, so it was a win-win for us as the components were just sitting in a closet in his apartment. But it got me back on the upgrade path, for now. But at least I can fund it with the proceeds of selling his e-waste.
The rest of my RAM should arrive today, so I'll have 64GB in the machine shortly. Plenty for VMs to run.
