A few weeks ago I needed a computer to be a Debian server for some at-home simple Web dev / learning stuff. I bought an HP Prodesk 400 G3 SFF PC with i5-6500, 8GB RAM and a 256GB off a popular auction site for £44. It'll do. I might upgrade to 16GB. An additional 8GB stick costs £19.
Good work. I bought an AMD Ryzen 3 3100 for €35 with shipping. A Radeon W5500 would set me back €150 at the moment. 16 GiB of RAM another €90. And that's on a relatively cheap site in my country.