How are you dealing with the current construction situation?

If the loan is fixed and the construction is (mostly) fixed at fixed prices, I wouldn't have any sleepless nights. Only those who are now going into planning and don't have a loan yet should recalculate everything...

We are in exactly the same situation as described by the questioner. I have to say that I have sleepless nights and would also advise others to call it off… at the same time, we are still pushing through. Financially, we did not plan completely at the limit, even though the increases hurt. However, we do not assume that prices will go down, as written above. The energy transition will permanently bring significantly higher energy prices, and if there is also demand for material due to reconstruction, it certainly won’t make things more readily available. Just due to the increased interest rates since we signed the contract at the bank, we have already saved ourselves a lot of money compared to a later date, despite default interest. That is one aspect that makes me at least somewhat positive…

No, it isn’t either. Therefore, you have to enter the contract negotiations very openly. Ideally having space to safely store material, etc.
Regardless, I would also clearly choose an air-to-water heat pump and photovoltaic system in large quantities. Additionally, make sure energy consumption remains low. That provides independence in summer and spring/autumn, and in winter you need the least from expensive or scarce energy.
Possibly also a mini pellet stove and a few bags of pellets. That covers a lot.

Unfortunately, a fixed price doesn't mean much these days. If the general contractor wants additional costs covered, otherwise construction stops, what choice does the client have?