Question of curiosity: why not consider RaspberryPi for the task? It is definitely going to be cheaper and more power efficient when comparing to mini computer (even if you take new one), because has so much more computing ability per Watt. I’ve been running HomeAssistant + cups server + small file server on RaspberryPi 3b+ without any issues for few years, and it was pretty actively used.
Additional point, RaspberryPi is publically traded company on London Exchange, and was founded in Britain, which mostly matches the “Buy European” motto ;)
Darn, you’ve just explained half of my life