You’re over complicating things, get some smart radiator valves ie https://amzn.eu/d/7ImsUuu
They will allow you to control temp room by room, they’re fairly simple to fit, just keep the original valve around and reinstall when you move out.
Controllable by Alexa/google etc, plenty of brand options around. Compatible with vast majority of rads out there, the valves are designed to be replaced easily.
It makes a lot more sense for blinds than curtains; blinds can be a bit of a pain to open on a conventional chain - I've motorised and automated mine, with power direct to the blinds (which was possible when rewired the house). Really great being able to open/close these with Alexa, and automate + group these. Was relatively cheap too, got majority of parts off of Aliexpress.