Comment by rpcope1

Just use some Reolink or similar ONVIF cameras like Axis or Dahua. Block traffic from them to anywhere other than your NAS. They're pretty simple, mine have the ability to just FTP captures to a given system, and thus I've got redundant captures (on a system with a bunch of drives, and on the microsd cards in the cameras). Maybe there's some spooky backdoor crazy way they can phone home, but I doubt it given how they're PoE and access to basically every other system is locked down my firewall.