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?
There is this great overview to find the Specs and all info about upgrading and stuff: https://www.parkytowers.me.uk/thin/
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.