Verdict
The €150-250 used ThinkCentre M75q running Hermes Agent is the cheapest credible workhorse setup in 2026. You give up some performance vs a current-gen mini PC and you accept the refurb caveats (worn fans possible), but for first-time self-hosters the price-to-capability is unbeatable.
Setup notes
Verify the unit on arrival: thermal throttle test, fan noise, NVMe SMART. Replace thermal paste if the unit is older than 3 years. Debian 12 + Docker + Caddy. Hermes Agent installs as on any Intel mini PC.
Performance
Idle: 8W. Under load: 28-35W. Older Ryzen iGPU keeps local LLM out of reach beyond Phi-3 mini class.
What breaks
- Local LLM beyond 4B params
- Sustained workloads on units with worn cooling
Want to know more
See the full Hermes Agent review and the Lenovo ThinkCentre M75q (used) buyer's notes.