Are the ancillary construction costs of the building provider realistic?

Something about the worst case. A colleague had to do pile green fertilization and thus had earthworks costs of 60,000 euros.

The house will be pushed in border development against the neighboring house, so basically a semi-detached house attached to a different house.

If the house is built directly attached, the neighboring house may need to be supported to prevent it from sinking. That also costs extra. Is there a basement there?

: I didn't notice that sentence at all

: Is that taken into account by the construction provider in the calculation? Especially because you write that the two building structures are not congruent.

So you pay €5,500 for all the specified earthworks/foundation, or do you pay this amount in addition to the planned amount X for the earthworks?

Yes, the €5,500 is complete, as 30cm soil replacement is already standard in the general contractor contract. That is very often the case with general contractors/building contractors.

Check with the local water authority regarding the approval for the recycling material. You may not be allowed to use it just like that under certain circumstances.

On-site storage means nothing other than that all the excavated material remains on the property. If you want to get rid of the amount of earth, you have to pay for the removal and disposal yourself. Although it says there that a slope is made for free, do you really want that? Such an extreme slope???

Regards