Thermostatic Radiator Valve worthwhile?

Ok, I was thinking of selling my house. As part of it I would of had to do a BER rating. To get an idea I read some BER reports off web and all of them recommended to install TRV's to heating. I was wondering would it help improve my house at all?

I renovated the house circa 2010/11. As part of that I put insulated slabs on external walls, new windows & doors. Put in new heating system with condenser boiler. Insulated under the floors and done the attic. Recently I replaced the standard heating controls with Climote so to turn on/off heating when not in house.

I also put in wireless thermostat which I put into what I think is the coldest room.

The house has 10 radiators which are all new but have the standard turn on/off. They have 1-5 option on them for heat into them but normally I just have on or off. 99% of the time all on.

Would the TRV save much money in regards to heating?

If I do sell the house would it have huge impact on BER rating?

Any idea of costs? THanks