Cost flat roof vs. pitched roof, exact details required

And why is that an argument for a flat roof? 2 full floors and on top either a pitched roof with additional storage space or potential for expansion (or directly expansion) or option b) would be 2 full floors, flat roof, done. The eaves height is about the same in both variants.

If the development plan allows it, then that is of course also a very good solution. However, I didn’t actually think of that first, since you don’t see it that often (at least I haven’t noticed it).

I always just come across something like this here:
xxx.von-emhofen.de/

For example, I looked more closely at the house in Köln-Brück for €995,000 (direct link does not work on the site). One of several deal-breakers was that there is no second full floor and that the entire 1st upper floor has sloping ceilings, which greatly restricts placing the furniture, etc....

For example, the Waldsee house from Gussek Haus is a variant with 2 full floors and an attic that can be well used as a reserve.