I've been using a Home Assistant Yellow, which is running on a Raspberry Pi CM4. Bit more specialized than the Green I think.

Honestly, to be fair, You can buy two more powerful 1L dell optiplexes or HP prodesks for this cost. i5-7/8xxx with 8G/16G ram often go for $40-50 on eBay.

Install proxmox and HAOS and you can use the rest for other stuff.

How’s the power consumption compare? If you don’t need more powerful it might not be the bargain it looks like.

Idle wall draw is approx 4W, average is approx 15W under load. Hovers around 10-24 mostly tbf. These are mostly i5-xxxxT CPUs. They have TDP of 35W.

And honestly, if you're in many states of the US - power's consumption is not necessarily an issue. Electricity is dirt cheap in the States, but I see your point.