refurb 7040 aren't too bad.. $275.00 free shipping

https://discountcomputerdepot.com/refurbished-computers/desktop-computers/desktops-for-business/dell-optiplex-micro-7040-intel-i5-2-5ghz-4gb-256gb-ssd-windows-10-pro/

https://www.amazon.com/Dell-Optiplex-Computer-i5-4570S-Bluetooth/dp/B07ST3YB1W/

search refurb micro pc's there are some good deals out there depending on the specs you need. I saw some for around $159.00 and up.

Guess the real trick is something that small you can put a graphics card into if the intel integrated video is not sufficient. Spec'd some Dell 3440's with i9 10 core processors here at work with nVidia quadro cards, but they came in around $1800.00 each when we were done. Will be ordering 10 of those soon for the design department