I hav started making my home smart home using raspberry Pi 3B & esp8266.
i am using openhab to control all devices & MQTT is protocol used to interface all esp devices.
currently 6 switches are converted in to smart switch & one RGB led controller designed & hoockuped with openhab which you can see in video.
i also have interface telegram with my home automation server for live notificaiton and it is working fine. hopefully i will install some PIR based sensor for motion deetecton in futuer.
I have designed my own circuits from scratch using ESP01, Esp8266 , Arduino.
System is up & running still last 4 month & my family members also liked it.
Finally decided to made all switches smart..
Hope getting succeed with all your wishes.
& thanks to every youtuber as i learnd everthing form youtube only.