I have a couple of setups, one has poe ip cams writing to a surveillance nvr which looks after motion detect etc. The other system relies on the camera software detecting motion and writing to a Nas.
Both systems are on their own subnet and are firewalled from everything else. I VPN as and when required.
I’ve found motion detect with alerts to be difficult to tune to get good detection without false alarms.
If it happened frequently enough, the government would find a way to tax it.