Need suggestions on my plan

The scope:
House size: 350 Sq. meter
Expected no. of IoT devices and sensors: less than 60 (I’ll start with 2 devices max)
TOP most priority: Local control. Nothing should be sent to cloud AT ALL. Solution should be cost effective as well.
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I am starting to convert from fully conventional home to Smart Home. After all my research so far, the kind of setup I am envisioning is:

  1. Run HA on a home server
  2. Use SONOFF Zigbee dongle-E as a gateway and for Zigbee2MQTT
  3. Use smart switches instead of replacing all the bulbs, fans, etc. by smart ones.
  4. For privacy purpose, separate out the IoT on network so that they cannot reach internet. They should only be able to reach local area network.
  5. In future, I might use Zigbee repeater in case of range issues with dongle-E

Please advise?

If you did not buy anything yet, I suggest the Sonoff Dongle P. It is better supported in Zigbee2mqtt.

  1. Ok
  2. I’d suggest a ZigBee Lan coordinator. More flexible in terms of location and less interference potential.
  3. Smart switches will (in most cases) only give you on/off control. You might need smart modules for things like fans & dimming.
  4. You won’t need this for ZigBee or if your WiFi devices are flashed with something like Esphome. Don’t overcomplicate matters for now.
  5. Most mains powered ZigBee devices are routers. The exception to this are no neutral switches and Sengled bulbs.