I had a place where the hot water did not work. Owner wanted photos of the hot water system, then told me that it’s working and there is no problem.

Sounds like a plan. I think I’m going to love it to death

I use Zerotier. I have a rpi sharing my Linux isos through a commercial VPN. The RPI has Zerotier as well as my other devices, so I can connect to it from anywhere as if it was on my home network.