I'm currently in the planning phase as well and digging up the thread again.
We are currently considering moving the office to the basement because otherwise it becomes too cramped on the ground floor. At the moment, we have the office planned on the ground floor with 12 m², but with 80 m² everything else gets a bit small. No pantry, kitchen, and living/dining room could also have a few more square meters.
Of course, you could enlarge the ground floor, but then the whole house becomes too big. If we, for example, go up to 85 m² on the ground floor, the total would be 170, which is already too big for us and, of course, also more expensive. Besides, the space on the upper floor is sufficient for us even at 150 m².
On the other hand, the study in the basement is not so great either. Since I work from home quite a lot, it would be much better situated on the ground floor. Additionally, we might want to use the room as a bedroom later.
Do you have any suggestions?