I want to upgrade my Pis to something more reliable and not SD-card based and refurbished thinclients/SFF workstations seem to be a viable route. Does anyone have a cheap source for used hardware like this in Germany? I feel like the usual esm-computer, green-IT etc. are a bit overpriced.
Okay yeah immediately the prices seem a lot more reasonable. Do you have a make/model/configuration you like to search for?
Make sure the description says the power cable is included. They usually take the kind of power supply older laptops took and when I bought a thin client to run home assistant the price difference between ones without and ones with the adapter was way less than buying the adapter myself.
There is this great overview to find the Specs and all info about upgrading and stuff: https://www.parkytowers.me.uk/thin/