Received an offer from a builder: Cost of shell construction - experiences?

Yes, that was the statement from the entrepreneur. Quote: If required by the soil survey, we'll just put in a ton more steel...

Bold to rely on a verbal statement; steel costs money. I am curious, if it should come to that – whether your builder will remember his statement about free adjustments.

Rhenish greetings

Twice the clause on proof means nothing else than that these items could cause surprises.

ALL (really all) essential agreements must be included in the written contract. Oral agreements are valid (if written form has not been agreed upon), but simply not provable.

You may still have the oral agreements documented in writing afterwards. A written confirmation from the contractor is sufficient for this.