Aaa cool!

So the pi zero with camera is just a other component not physically connected to the doorbell? And you use mqtt to make them “talk”?

Well my setup now is:

Pi3 with HASS

Pi3 (no purpose yet)

pi Zero (non wifi)

Cheap RF doorbell (I dont know if it will work)

I orderd:

Pi zero case

Pi zero camera (cheapo)

433Mhz Wireless RF Transmitter Module+ Receiver

Cables to connect wifi dongle and other stuff.

Maby need to buy an other doorbell because this one is not that good.

Do you have HASS installed on a RPi? And is this also your MQTT server and RF?