Building an end terraced house - Which technical requirements should be considered?

And exactly what I actually wanted to avoid happens. It leads to unnecessary disagreements:

The other corner house absolutely wants to enforce its 35-degree roof pitch, as a change would cost almost €4000. However, from our side, 35 degrees is not possible because then we cannot fit our air-to-water heat pump into the utility room under the roof.

A proposed compromise of 37.5 (is ,5 even allowed?) is actually not desired, since "it brings no benefit." Annoyingly, the corner house believes it should set the standard here, which the others then have to adapt to.

Does the slope have to be the same for everyone?

Does the slope have to be the same for everyone?

Yes, exactly.

Couldn’t I submit the building application or preliminary building inquiry in front of the others?

Couldn’t I submit the building application or preliminary building request in front of the others?

We could – however, the municipality wants everyone to discuss and agree. We are going to the building authority again today – let’s see what they have to tell us about it.

Well, I'm curious to see what the community does. Will it side with a developer (arbitrarily?) or be flexible itself and accept inconsistent slopes...