For the aftermarket firmware that allows non-ChromeOS OSs, theres a compatibility list at https://mrchromebox.tech/#devices https://mrchromebox.tech/#devices th

For the aftermarket firmware that allows non-ChromeOS OSs, theres a compatibility list at https://mrchromebox.tech/#devices https://mrchromebox.tech/#devices that will show you if full UEFI firmware is available, and the write-protect method you need to disable. I usually browse around Mercari looking for a system with specs that are acceptable, then check the list to see if its supported. I haven't paid more then around 50 bucks for any of them.