Construction costs are currently skyrocketing

Butt heater is a good keyword. I once read that it even consumes less fuel/energy if you only turn on the seat heater in the car (alone) and keep the other fans off or cold. Is there any truth to that?

Yes, that is THE recommendation to increase the range of (fully) electric vehicles. Steering wheel heater and "butt" heater on, normal heating/air conditioning off. Gives me about 10-20 km more range in winter despite the heat pump for heating.

I’ll try Tripper soon… oh no… Tibber. I’ll keep an eye on how the prices develop. The cancellation period is only 2 weeks, so I don’t think it’s much of a risk.

The catch with awattar/tibber is the initial conversion to a smart meter. That can apparently take quite a while.
Smart meters are also expensive (€100 p.a.) and that cost remains, unless you switch back if you want to turn your back on these providers.
Of course, sooner or later we will all be forcibly burdened with smart meters and the costs... but personally, I wouldn’t provoke that.

Yes, that is THE recommendation to increase the range of (fully) electric vehicles. Steering wheel heating and "butt heating" on, normal heating/air conditioning off. For me, that adds about 10-20km range in winter despite a heat pump for heating.

Absolutely, seat heating consumes a fraction of the electricity compared to heating the ambient air.

Hmm, my wife always uses both - now full blast. She doesn’t trust the automatic settings either. Always manual on the highest level for heating and fan...

And after 15 minutes she’s of course too warm and what does she do then - exactly, opens the window... :p

Does your wife also set the fridge to the highest level when it's hot in summer?

Does your wife also set the fridge to the highest setting when it’s hot in summer?

She then cleverly cools the kitchen with the fridge door open ...

For my wife, refrigerators don’t need adjustable settings. They should always cool at maximum, period. But when it comes to the fridge, I’m almost the same... Nope, you can’t leave it open, because it beeps. ;)