What must be included in the purchase contract with the developer? Redevelopment area, cultural monument?

Yes, that's correct, but the building application has already been approved by the city / district through the developer.

Well then, you know the part of the house that is approved and will be built as approved. Do you really want to know all the details from the developer that he discussed with the office on the way to the building permit?

Well then you know the piece of house that is approved and built exactly as approved. Do you really want to know all the details from the developer that he discussed with the office on the way to the building permit?

That is true, however, due to the cultural heritage monument in the immediate vicinity of the property, an application must always be submitted to the authority, for example when it comes to roofing the terrace.

I consider it relevant to inform us of this from the seller’s side before purchase, or not?

Do I already consider it relevant to inform us about this from the seller's side before the purchase or not?

I agree, I would have done the same as a seller, as mentioned above. But now? You know, it is what it is, what do you want to do? Not buy the house? Otherwise, you seem to like it somehow, otherwise you wouldn't have commissioned the notary for the purchase contract. The developer will surely find another buyer ...