We have designed KC868-A8S esp32 board, many hardware resource for you to use. it support GSM module for SMS, voice call, GPRS communication. Use SMS or call to turn ON/OFF relay will be very easy for home automation DIY. You can write any code by Arduino IDE to ESP32 wifi/bluetooth/ethernet RS485 module. We will supply demo code for different samples. Everyone can modify and change the code for your own smart home automation system project. it support use by ESPHome for home assistant or tasmota firmware for smart home automation DIY.