[morzh]

I learned long time ago that when I think of a product, it has been made by somebody and is being sold.

In mh first house, which was 1-zone heating/AC, I thought of "what if I could have a movable thermostat with a radio connection to the base, that hooks up to the regular thermostate wiring; I would then be able to move the thermostate in the room where I want the temperature to be kept".
Next thing (it was 2006) I knew, I decided to see if it had been made by someone.
Sure enough. Not superpopular, but it did exist, and I bought it and used it for the next 9 years.

So, the lesson here: if you need something you want to make yourself, see if someone has already made it and if it is affordable. It is almost 100%.