To come back to the original topic here:
I am still waiting for the exact price from Probau, but I have an approximate value. And I have received a similar price from another company that is very well known in our region. So this company is definitely not the only one that calculates prices like this. Yesterday I spent 3 hours with the consultant of this company going through every detail of the construction description, including the services included, etc., and so far I have not found any disadvantages compared to other companies.
Regards Daniel