Floor plan of a single-family house with 240m² including a 75m² granny flat and garage

That was the goal. To make division into four units possible. At least that's what the OP writes. It looks that way too

That's wishful thinking. Far from any reality. Do you then want to retrofit stairs, change entrance areas, conjure up parking spaces, etc.? Much more has to be invested in the planning.

That is wishful thinking. Completely detached from any reality. Do you then want to retrofit stairs, change entrance areas, conjure up parking spaces, etc.?

Now don't confuse things here with reality and its facets.

More investment must definitely go into planning.

Preferably expertise, a lot of time is already invested anyway.

More effort needs to be invested in the planning.

Don't say that to me. I did not plan the hotel corridor.

That is wishful thinking. Completely detached from any reality. Do you then want to retrofit stairs, change entrance areas, conjure up parking spaces, etc.? That requires much more investment in planning.

Another staircase is not needed. You can box it in at the bottom and top. Then you always have 2-3 rooms and a bathroom that you can separate. So, the loft would still need to be expanded downstairs, of course. But theoretically it works if you think you have a living unit when you have a bathroom. Addendum: Just because I (also) understood it does not mean I consider it livable and worth building.

I am planning a house for up to 7 people, sorry that my family planning does not fit into your scheme, but I plan according to my ideas and the architect has considered all my requirements, wishes, and ideas, which another architect rejected in the preliminary discussion.

The architect is both an architect and a structural engineer.

A little something about me, I am not a convertible Porsche driver like most here, but a minibus driver in the basic version.

A little off-topic because this forum probably should be renamed:
I am happy for you that you have not yet experienced the following risks. Separation after taking out a loan, e.g., planning phase, execution phase, completion phase, move-in phase, adjustment phase. Selling the house because the children's rooms are not enough (another child/double happiness), new partner, different profession, job loss, caring for relatives. Change of workplace. So according to your "expertise" shown here, one should only start building a house or even planning if this is 100% excluded, many thanks...

I have to agree with @Gerddieter here. I can mention that some doors are poorly... positioned, also that the granny flat gets better space utilization if the entrance is placed sideways, or the common rooms are not planned almost square, but if you already poorly plan the guest room and also realize that this room can hardly be used as a bedroom, why on earth don’t you plan this room better? There is enough space...?! And why should one feel comfortable in a bathroom that is not even 4 sqm when old?

The granny flat is modeled after Virtus Massivhaus. If you rotated it, it would not be compatible with the plot.
Unfortunately, I don’t understand any of your inspirations. The guest room is for guests, not for old age. If that were the case, it would probably be called an old-age room. When I become old and gray, I would move into the granny flat, same with the bathroom. It is only for the first two years and then at most for guests, but I suppose an open bathroom directly in the living room would naturally be better for you?!?
Sorry YPG, I will not comment further on

How big / tall are the houses in the area?

The neighboring buildings are 8.7 meters and 9.8 meters on one side. On the other side they are 11.6 meters and 11.7 meters.

That was the goal. To make subdivision into four units possible. At least that’s what the OP writes.
It looks that way too

Yes, exactly, the goal was to design everything modularly.

That’s wishful thinking. Far from any reality. Do you then want to retrofit stairs, change entrances, conjure up parking spaces, etc.? More has to be invested in planning.

Um, okay, maybe you understand “subdivision” differently than I do, but the subdivision is obvious. Depending on the division, only short drywall partitions with doors must be installed, but I understand that you have never seen or even done something like this. Parking spaces really, aren’t 7 parking spaces enough for you? Should I plan 14 parking spaces for 7 people or rather 21 parking spaces?

It’s a pity that so far only one person has mentioned the chimney, called it a fireplace, but at least he tried...
Maybe someone will still say something about ceiling height or parapet height over the weekend. I’m curious.

You are very presumptuous, you know that?
And you are very unobjective. On what grounds do you insult and accuse this forum or the forum members of having a Flower-Power-Gucci life?
You don't know anything about us. You don’t ask, that’s okay.

You want help with your house project.
There is a questionnaire here that is created to find out something from the OP, in this case you, whether the project is also usable for that person.
Just because you don’t understand or can’t implement answers, tips, or suggestions, you think you can lump everyone together under one and the same brush.
There are also some here who are dealing with divorce, widowhood, grief and hardships. But whatever.
Keep going like this, and you will turn the help of a forum against yourself.

...

The guest room is for guests not for old age. If that were the case, it would probably be called an old age room.

I didn’t write "old age." But you explicitly mentioned that you don’t like that the office cannot be used as a bedroom.

Office downstairs is only possible as a bedroom if the cupboards are under the stairs.