Offer(s) for a new building

It’s not the first time I’ve read "too cheap" from you, whether it’s shell construction, garden, terrace roofing ... Either you simply have a completely different price level or you have a big heart for craftsmen. Because in my experience, these statements are consistently wrong. Just recently completed a flat roof construction, 2 floors, 195 sqm living space for 75,000€ shell construction. Completely in sand-lime brick. In NRW. Added to that are 25K€ for the facade (WDVS) and 10-15K€ for the roof. A neighbor spent 150K€ for shell construction on 250 sqm living space, integrated garage, full basement (130 sqm), monolithic, perlite-filled Poroton, KFW 55. Just for comparison. But that’s basically the top level and hardly comparable with the usual ....

or rather he said that he always uses a 27er for his constructions

.. what kind of professional is that ..

You can't see anything in the pictures.
What is supposed to be included in the 55k€? For what size of house?

So, should the discussion continue here or not?

Our structural engineer's task was to calculate as cheaply as possible. A 27 cm ceiling costs more than 20 - 20 was sufficient statically, so why take more?

In the other topic, you expect people to fiddle around just to be able to read your documents at all. If I were you, I would have at least tried to upload them in a more readable condition.