Very relative. I paid 10 euro's for my last RFLink. And 2 minutes of my time soldering the little antennas to the receiver and the transmitter. Connected them up with some dupont cables flashed the firmware put it in a box, hooked it up. Cheapest transmitters and receiver I could find on ali, still ...

Stuntteam, will do!!! ... both links. Quick question on the guide: Can the Raspberry Pi be replaced with a Synology? I have a Raspberry Pi but have actually installed Domoticz on my Synology DS215j.. so would the Arduino Mega run on the Synology making Step 5 look like this: "Connect the Arduino ...

Great to know.
I am new to Domoticz and this kind of information is very useful.

I guess that no matter how "plug & play" the devices are you need a receiver to collect data.
Can you write a few more lines on what other devices you use to make your system work?

Thanks!