My IoT stuff has grown somewhat haphazardly and currently uses a mix of random protocols. I'm now trying to design something a bit more... coherent.
I had more or less settled on z-wave as the best protocol to use, but for all the benefits of z-wave, it's really expensive (though I appreciate that it may still represent good value). For example, locally sourced (RSM compliant) fibaro and aeotec light switches are like $100. Compare that to ESP8266 based stuff like sonoff that is less than $10 for the same functionality.
But obviously having dozens of wifi devices in my house is going to start to run up against the laws of physics and run the risk of performance issues (hi @sbiddle!). I've got 3 Cambium E400 wifi APs (suggested limit, 127 devices per AP, max limit 255) and I'm pretty confident I will have less than many IoT controllers. Perhaps a bigger issue is a router that will handle all those devices. I see "IoT routers" are now a thing. The ISP-supplied HG659b's 32 device limit won't cut it though. Frankly though I could buy a pretty high end router (or two!) for the cost of a dozen z-wave light switch controllers on their own.
Has anyone else got/started an automated home based on wifi? Did you separate your networks physically (maybe a dedicated router)? How many devices is a realistic limit?
If money were no object, I would definitely be going z-wave (though if money were really no object I would be thinking about an ethernet cable to every lightswitch, bulb, power socket and appliance in the house. That would be a *big* patch panel).