Sometimes transformers lose a neutral or something I think it's called and can fry equipment. Should have everything on a UPS anyway. That would help a lot I'd suspect
But it can also mean there's wiring issues in the POE run. Like excess static charges etc
There's multiple ways to do it. Any computer basically can run Wireguard. As well as Zeroteir, Tailscale, Twingate, Openziti and more...which all are based on Wireguard. But arguably easier to set up/manage. I went the open router option which has the option to use Tailscale as a pkg as well as OpenVPN and I also have a Zeroteir connection I can use. One of the easiest is run Zeroteir on a device on your local network and on your remote device to default access and share remotely. You can change some settings to switch it from a split vpn to a full tunnel if you want depending on your needs.
Theres open router operating systems like OpnSense that will run on about anything and allow running of Tailscale right on the router giving full network access if desired without any extra systems running.
In tailscale it's similar and just needs a bit more configuration to setup the local network as the exit node. That will allow full tunnel to it so remote devices show like you're home. But you're limited by the upload of your home internet. If you want to be split, you can just select to disconnect from exit node and it will be split so normal speeds of your internet wherever you are remotely. But network traffic still runs over the Tailnet. So it's easy to switch back and forth.