Start of house construction / Foundation slab is being laid / Tips

The time you spend on your negative comments, treat yourself to a hot tea and enjoy your free time.

That is provocative. At the age most people here probably are, one should know that. After your last answer, you have disqualified yourself anyway. Expecting something like "go die" or something similar now, I will continue to watch the thread with anticipation.

I have also attached the construction of the base slab according to the Energy Saving Ordinance calculation. It mentions an exp. PS foam_035 after the concrete. However, I did not see it being installed at my neighbor's place. - Should I insist on it?

Yes, however, it is usually only installed after the underfloor heating (if present) and the screed have been laid. So there is still time for that. For safety reasons, I would still ask about waterproofing against rising moisture, as in my opinion that belongs between the base slab and the masonry or pipes and the aforementioned insulation.