New single-family house on sloping plot

Transport and landfill are not explicitly included. Clearly a point that probably needs to be clarified.

Perhaps it does make sense after all to consult an external architect.

Transport and landfill are not explicitly included. Definitely a point that needs to be clarified.

Congratulations, that’s at least +20k€ now. I built in Middle Franconia. There, 20€ per cubic meter is usual for Z0!
What about the remaining construction additional costs?

Unfortunately, quoting is not possible because you wrote in my quote.

There is a basement (just like in your plan) and a lower ground floor with living spaces.

Is the drawn slope the natural gradient?

On my parents' street, someone used the garage and the stairway as a retaining wall and built the house without a basement on top of it.

The disposal will not be easy.

I would not submerge the garage. Cloakroom, utility room in the basement. Staircase as proposed in the east.
Make better use of the lower ground floor and reduce the footprint.
Plan the terrace behind the house.

The entrance is not dark because it is illuminated by the window on the ground floor. It is narrow, you are right about that.

It wasn’t me. Still true. Behind the stairs is only dark.

Maybe it makes sense after all to consult an external architect.

Try it with external architects and/or additional general contractors, collect ideas. Where are you building?

Right in the northeasternmost part of Bavaria!