You might want to have a look at this:
https://www.rtl-sdr.com/tag/433-mhz/
and/or this:
https://www.rtl-sdr.com/tag/rtl_433/

With rtl_433 you can send out a MQTT message to domoticz to the TFA rain device (create with hardware/custom sensor)

If you have a Fronius Inverter (ie IG/TL 4.0) combined with the older datalogger, I just made a very simple bash script to read values from it.
If you are interested have a look at:

https://github.com/HanSyt/Fronius-Datalogger-2-Domoticz

ZoneMinder works, but indead it takes some cpu on a hres camera.