Here is a composite picture of GDO endeaver with modded Sonoff Wifi Basic.
Note here the current GDO stuff is hard wired to the Omni Pro 2 alarm panel zones (~ 150 - 200 feet) to the central wiring zone - all analog.
There are no failure points with the alarm wiring.
Using powerline, powerline hybrid or wireless introduces failure points and (X10, UPB, ZWave, Zigbee or WiFi) network (POE, Switch).
I do not depend on wireless X10, ZWave, Zigbee or Wifi for any hard security. That is me.
The vehicles have small wireless RFID tags which ID the vehicle to the house. I don't utilize these tags though relative to the alarm panel.
It is much less wiring using Sonoff but the dependency is on wireless here.
With this endeavor the SonOff WiFi device plugs in to the outlet above the GDO and is hard wired to sensors and GDO plus temperature sensor.
Signal strength from SonOff WiFi basic is around 60% to one test WAP centrally located on the second floor of the two story.
There are more pieces relative to transport and to be dependant on.
Using triggers and events to post logs and text to speech I do not notice much of a difference between response times to the Sonoff versus the hard wired alarm zones triggers and events.
This is an el cheapo solution using a $5.00 modded SonOff WiFi basic module and a little DIY time. ~ less than 2 hours to build and test.
Multiple functions of Sonoff:
1 - Door open sensor
2 - Door close sensor
3 - door trigger open close relay
4 - temperature sensor
5 - door to house or exit of garage door sensor *
6 - windows sensor *
7 - PIR sensor *
* adding use of more GPIOs and or looping the sensors.
The device / arduino is a sort of single purpose computer with it's own IP address. Here is a picture of a different firmware doing the same stuff on a SonOff. This firmware allows telnet and using a static IP and has custom pieces in it for a variety of open source automation.