Well, I run a server in China. I have managed to lose contact with the servers in numerous occasion, primarily due to my own stupidity. So I desperately need some sort of out-of-band management solution (OOBM). Primarily there are three ways to achieve this. I have listed them in the order of how easy it is to test then out.

1. USB Serial adapter that gets activated at GRUB time / when kernel gets loaded. The serial console can be tested in a Virtualbox VM, by configuring a serial host pipe. However this approach does not test the driver complication - to investigate that, I would need to connect a USB serial adapter to the VM, another one to the physical machine. This can get a bit confusing quite quickly.
2. Raspberry Pi Zero W Virtual HID Keyboard + Skype. This idea requires the purchase of a new Raspberry Pi Zero W. I can't use the old Raspberry Pi Zero, as they have no network connectivity.
3. Intel AMT 6.0+. This is probably the easiest but most expensive option. A cheap source would be old laptops, but then I cannot guarantee they have vPro, and even if they have vPro, I cannot guarantee that they are not permanently disabled.