GU does not guarantee KfW compliance. Cost risk to the customer?

That is also my thought, that the risk somewhere between 18,000 and 26,500 euros would then be entirely on me, without me being able to influence the outcome. Then that is not stated in every offer, but rather the exception (or a single case)?

then write in that you will get the surcharge back^^ you also have disadvantages regarding the financing

Is your house planned so unfavorably?

then write in that you will get the surcharge back^^ you also have disadvantages regarding the financing

Do you just accept the disadvantages then?
What does the general contractor care about the financing?

Is your house planned so unfavorably? Do you just accept the advantages like that? What does the general contractor have to do with the financing?

What kind of views are these? The customer pays an extra price for a standard that he compensates for through financing

The surcharges for the Energy Saving Ordinance/Building Energy Act on KfW55 or from the Energy Saving Ordinance/Building Energy Act to KfW40 are each listed separately as optional surcharge items, but both with the aforementioned note that no guarantee is given in the end for compliance.

What about the house? You are paying for a house, did you get the guarantee that it will be one? :-)

What kind of views are these? Customer pays a surcharge for a standard that he compensates through the financing

If you don't like something, you don't buy it. Simply not paying afterwards is a no-go.

Simply not paying is not an option. I just have to consider whether this is an exclusion criterion that generally prevents signing the contract. With the surcharge and funding, it's about 30,000 euros after all. If I order a new BMW, the leather seats cost a 5,000 euro surcharge, and BMW then says "we don't know yet whether the cow feels like cooperating that day or whether there are enough cows, it might also be that in the end there is no leather," no one would order and pay for that either, but would expect BMW to have its procurement and production under control so that they can either offer it or not. Or is house construction a significantly higher complexity and excusable?