I first found the technology in 1981 and used it in my house. I used R.S.,Sears, and other brands and amassed quite a collection of pieces/parts including plugin modules, timers, keyboards and remote dry switches [which I am not sure if they still make them]. Most I found at yard sales and flea market from people who didn't use them.
I used a dry switch in my basement to turn on a light "up stairs" when the sewer backed up or when it rained and the basement flooded. In 1992 I used the system to turn on, off, and dim the stage lights for a local band until I could afford a real system. The only problem I had was the time delay between button push and response to it. My son bought a garage door opener but the electronics for the remote opener was shot so I used an in/out dry switch combo and the remote transmitter/reciever for the house.