Floor plan of a single-family house on a hillside with a basement

That may be true, but I wouldn't go to an architect who then draws it like that again. Any architect with a bit of pride and idealism for their profession would refuse to be involved with that thing.

If that is true, the thing with the architect. After all, we all know that this is actually not the work of an architect. And everyone would say goodbye to him and choose someone else before that crap even gets discussed. Operating the program is one thing, an inexperienced person can get frustrated. But there are also some big mistakes in the skilled craftsmanship here, which older generations should especially be able to handle ;)

Regarding the missing stairs to the attic floor:

At first, I didn't think much of it; my first association with these lines was a plan showing foundations and a pool ;-)