[thangalin]

Barring major technical glitches, installation and configuration of a reliable locally hosted Zigbee-based solution is on the order of two hours.

https://www.youtube.com/watch?v=GJEwrSSFe9s

Here's what I used:

    Raspberry Pi Model 4 B
    Raspberry Pi CPU
    Raspberry Pi CPU heatsink (w/self-adhesive)
    Raspberry Pi manual
    Raspberry Pi A/C adapter
    Raspberry Pi case
    ConBee II Zigbee USB gateway
    USB ADATA Micro SD card reader
    USB cable
    Micro SD card (for operating system and Home Assistant)
    Ethernet cable (probably not needed because the Pi 4 has onboard WiFi)

Thermostats: https://www.sinopetech.com/en/products/thermostat/

I haven't tried running a local text-to-speech engine backed by an LLM to control Home Assistant (HA). Maybe someone is working on this already?

TTS: https://github.com/SYSTRAN/faster-whisper

LLM: https://github.com/Mozilla-Ocho/llamafile/releases

LLM: https://huggingface.co/TheBloke/Nous-Hermes-2-Mixtral-8x7B-D...

HA: https://www.home-assistant.io/

It would take some tweaking to get the voice commands working correctly.