Floor plan of a bungalow with 140 sqm - does the storage space fit?

At least a fixed staircase facilitates the effective use of the attic. See report (subsequent request) and also see and , who implemented this in their bungalows, as far as I remember.

Hipped roof

That makes the attic gigantic

I can't understand that. I also have a hipped roof (voluntarily back then) and I believe that with a gable roof I would have about 30% more storage space due to the then higher roof line along the ridge towards the gable walls. Or am I imagining it too simply?
In any case, I regret my decision for the hipped roof back then. On the one hand because of the storage space, on the other hand because less photovoltaics fit on it.
Visually, I now think that hipped roofs are also way too fashionable, which stimulates my rebellious streak.

At least a fixed staircase makes effective use of the attic easier.

We have intentionally not installed one, it shouldn't be too easy to clutter up something. After clearing out and decluttering the cellar in the old house, never again. Now the ladder comes down every 4-8 weeks and we go up (mostly to bring down chairs for parties).

Fixed stairs were also a topic of discussion for us yesterday, but I also find it unnecessary to have a staircase (in the way) just for storage space. That might still change, but that's how I see it right now.

Then I ask where [Trockenbodenbinder] stand in terms of price.

I can’t understand that. I also have a hip roof (voluntarily back then) and I believe that with a gable roof I would have about 30% more storage space due to the then higher roofline along the ridge towards the gable walls. Or am I imagining that too simply? In any case, I regret my decision back then for the hip roof. On one hand because of the storage space and on the other because less photovoltaic fits on it that way. Visually, I now find that hip roofs are also far too trendy, that stimulates my contrarian.

Yes, sorry, I forgot to mention that we have a clipped(!) hip roof. Because of that, 2 sides obviously offer significantly more space. But apart from the 2 clipped hip sides, the roof pitch would be the same except for 1 degree. Friends of ours virtually built our house again with a hip roof. The resulting attic is very similar. Personally, I find such a steep hip ugly without the clipped part, but to each their own taste.

So you mean more
[Krüppelwalmdach] vs normal hip roof -> more space
[Krüppelwalmdach] vs gable roof -> nicer, because the gable is broken up?

Ok, the first is probably true, the second is a matter of taste.