I did minimal hardware DIY for temp/humity/pressure, with some Adafruit ESP32 boards and BME280 sensors. The inside unit has one of their e-paper displays to sh

I did minimal hardware DIY for temp/humity/pressure, with some Adafruit ESP32 boards and BME280 sensors. The inside unit has one of their e-paper displays to show inside/outside info, and sits in a box from the dollar store. I'd think that adding the other sensors would be minimal other soldering for added bits, but I haven't gone there (yet). [Edit: this could be non-soldering with a breadboard, which my outside unit is still in, with a battery and in a soap dish with holes added.] The more DIY side of mine is all the software, with MQTT as the glue. Both ESP32s publish to that, one subscribes (to show both), and a little daemon on the Pi with Mosquitto writes it all to an Sqlite database.