Just over a year ago I bought a 5950x on sale and with the help of some spare parts, and some great second hand deals I put together a Proxmox machine and began self hosting some services. 1 year later I have 4 Proxmox nodes; a 5900x system in the Rosewill rackmount case and 2 Beelink mini pc's.
I recently bought the Startech rack from a small business that no longer needed it. It came with 3 shelves, 2 APC rack-mount UPS's, one of which had brand new batteries, an HP Proliant DL6360 Gen 8 (not pictured, haven't made use of it) and a QNAP rack-mount something or other with 5 x 2TB drives in it. All for less than the price of the rack brand new.
Throw in a couple raspberry pi's, one that's running PiKVM hooked up to a 4 input HDMI switch, and one I use as my bastion host / jumpbox, and you got yourself a homelab!
Late reply, but I've got 4 proxmox nodes. TrueNAS with an HBA passed through, the arr stack, jellyfin, Home assistant, Nextcloud, bookstack, Unifi network application, Kavita, a windows VM with a 3080ti passed through that the kids can connect to using moonlight to play games on various tvs/devices. Various Linux distros to play around and test configs before I make any serious changes to my main desktop. Most recently set up graylog to pull in logs from pfsense and Unifi.
I have an insatiable thirst to just learn!