Cutting out the house roof in the garage area - experiences

The "gift" is probably just a mistake that happened somewhere (possibly also incorrectly entered in the execution planning?). And now you're supposed to be properly happy about his generosity...? Am I the only one who finds it strange that it is so often argued that his program draws something wrong? There is a person sitting there who should be able to correct it. Sorry, I know this doesn't help you at all right now and might only push you further in a more negative direction. But I have the impression that the company should be watched very closely and questioned even more often whether all parties are operating from the same assumptions. :-(

What else is a layperson supposed to pay attention to? We really read a lot beforehand and took many notes on what to consider. But questioning a drawing program was not among them :-) Something like that can only be endured with gallows humor...

What else is a layperson supposed to pay attention to?

With the 3rd house, it usually works out quite well :-)

Explanation from the general contractor: The Arcon program automatically draws a knee wall to be able to represent the eaves height. (Does anyone know about this? Is that true?)

But questioning a drawing program was not part of it :) Such things can only be endured with gallows humor...

Even if the CAD software has a bug, that does not exempt from the fact that "approved" and "built" have to match.

In case of doubt, the approved planning applies. That it is not a residential attic weakens your "injured party position" regarding less height in the attic. But no additional effort may arise for you from the unsolicited gift of the larger roof overhang. In any case, the builder is a gifted excuse inventor ;-)