Hardware recommendation room with many valves

Hello All,

I just started using home assistant in private and I am really happy with it.
I myself am searching for fitting thermostats for my flat but that shouldn’t be the main topic here.

In the building of our community there are several rooms that I like to integrate in home assistant as well to get smarter heating and safe some energy. The problem is that there are many radiators per room. In the biggest room we have 8 radiators so buying e.g. a tado system would be really explensive. Now I found out that termal actuators are actually much cheaper then thermostats and in my case I want to control the central temperature so there is no gain in having a sensor at every radiator. Could you give me a recommendation if there is a good way to solve this?

by the way, im not a native speaker and home I translated the terms correctly, if not feel free to correct me.

kind regards,
Gerhard