The one I use is this: CC2652 ZigBee coordinator or OpenThread router from slaesh's iot stuff and other hacks :) on Tindie running on my Raspberry PI 4.
But you can choose from many supported adapters: Zigbee2MQTT
Colleages of me are running Conbee´s and are happy with it, too.
I won´t recommend the CC2531, for me it was not very reliable when using Zigbee 3.0 Support.
The coverage depends on your Zigbee network. You can have some Zigbee-Bulbs that act as a zigbee-router/repeater without any additional hardware, or use one zigbee2mqtt instance per floor reporting to your central mqtt-broker.
I used the original Xiaomi-Gateway before, and it was very reliable and could run without cloud. But when Xiaomi brought out their Zigbee 3.0 Luminance Senors they were not supported on this gateway.
I switched to zigbee2mqtt and never regret it.
And about the accuracy:
- Temperature detection range: -20 - 60 Deg.C ( + / - 0.3 Deg.C )
- Humidity detection range: 0 - 100pct RH ( + / - 0.3pct )
- Atmospheric pressure detection range: 30 - 110KPa ( + / - 120Pa )
That is from the data-sheet, but for the temperature I think I can say it is in this range.
Kindest regards,
Christian…