I like the tapo series. If you got an installed doorbell (16Vac), the included transformer will provide power for 24/7 operation. The push notification is a distinctive tone, similar to a cellular call (besides a simple message notification). The battery version, will be active only during detection/button push, in order to conserve battery.
Yes, check the tapo d-235 model. Since is hardwired power, it will record constantly into the microSD card. Check a YT review for this particular model. You may watch the live video through the app called “Live view anytime”
As a simple solution, a Tapo D235 for example includes a built in battery, whilst supporting being wired. It will keep itself charged to 80%, and records (constantly) to a local SD card. It also supports being run entirely locally after activation if you really wish, though not desired in your circumstances.
You can also turn on the LED to show whether you're using the camera or not, or have it constantly off.
You can optionally buy a Tapo H200 Hub, record to that, and also use it as a Backup network connection by plugging it into a network device that supports 4G/5G; although ideally your main router should be upgraded to support that instead. A lot of Asus routers support 4G/5G backup over USB for example. Of course you'd need a UPS or some sort of battery powered solution for those backups.
captainmongo
