Floor plan, not a specific single-family house, approximately 200m² with 2 apartments

I thought so too at first. But to the right of the garage, a staircase leading onto the garage is planned, and from the garage a front door for the upper floor apartment is drawn. The technical room can also be accessed from the outside through the garage.
It is possible that the plan is to lock off the staircase later.

However, after the answer, I am no longer sure if this was thoroughly thought through until the end.

Yes, that was exactly the plan and I also wrote it in my creation thread.
The staircase can be securely locked with a sliding door at the ascent. The balcony door on the roof terrace
is supposed to serve as the front door (all furniture is also transported to the upper floor through this). You can reach
the roof terrace via an outside staircase.
The utility room with the washing machine as well as the garage should be usable as a common room for the ground floor and upper floor.
Here, on the ground floor, you can also lock the door to the utility room.

So, I haven’t read something this bizarre in a long time.

Of course, in the example-Flair you would enclose the staircase just like you have already enclosed your staircase. In the standard version, simply move the kitchen entrance slightly further up on the plan, then in case of separation you can just build a wall and actually use the staircase as an access. With your idea of external access you have to plan the property to be 3 meters wider.

And of course, upstairs in the variant with an additional room you can plan an apartment door .. just enlarge the exterior dimensions of the house as far as you have planned your house. That creates plenty of extra space. And, by enlarging the Flair 152 from now 10.5 x 8.75 to your 11 x 10.5, the office on the ground floor can also become so big that it can directly turn into a bedroom in case of separation. Then you don’t have to do anything in the living area. Etc. etc. ...

Such a proposal as a basis is just a basis that then has to be developed, where one or the other wall sometimes has to be adjusted.

EDIT:
in your variant using the washing machine in the utility room on the ground floor also for the upper floor .. carrying the laundry there via the outside stairs? No ... no.

Listening is probably not your strength? You seem to want to discuss every nonsensical answer. Just take what is important to you with you. Otherwise, you should think about why the experts are leaving here. To the many really well-intentioned suggestions, here is one from me as well. Read up on building regulations, planning guidelines, learn to read and evaluate development plans. Only then buy your plot. Of course, you can also ask the experts here for help. But then it is always better not to come across as a know-it-all. If you then want to plan your floor plans DIY (you're not the first here), then we can think about it again. Sorry for the eyestrain. But you notice yourself that your plan is really not good. I'll spare us both the lengthy criticism.

Well, I haven’t read something so absurd in a long time.

Of course, in the example Flair, you would enclose the staircase exactly as you have already enclosed your staircase. In the standard version, simply move the kitchen entrance a bit further upward in the plan, then in the event of separation you can simply put up a wall and really use the staircase as an access. With your idea of external accessibility, you would have to plan the property about 3 meters wider.

And of course, upstairs in the version with the additional room you can also plan an apartment door... just enlarge the exterior dimensions of the house as much as you planned your house. That creates plenty of additional space. And, by enlarging the Flair 152 from the current 10.5 x 8.75 to your 11 x 10.5, the office on the ground floor can also become large enough to directly turn into a bedroom in the event of separation. Then you don’t have to do anything in the living area. Etc. etc…

Such a proposal as a basis is just a basis that then needs to be developed further, where here and there one or the other wall may also need to be adjusted.

EDIT:
In your version using the washing machine in the utility room on the ground floor for the upper floor... carrying the laundry there via the exterior stairs? No... no.

I never wrote that it’s not possible, but that it is more difficult. In this case, probably a double door would come into play, which would then stand open all the time, which looks ugly and additionally restricts access to the staircase.
Yes, in this floor plan a door on the upper floor would be more sensible and possible, but with my spiral staircase it would not have made sense, since you would then also have to extend the railing all the way up to the ceiling.

I am aware that the property would become wider. If that is not possible, a spiral staircase or similar could also be considered, although it would be more difficult regarding moving furniture upstairs. Another idea is to have the garage partially adjacent to the south side of the house and then extend somewhat over the house. Then the staircase could run along the east side wall of the house. These are all things that could or would only have to be implemented with a real property.

Yes, that would also be conceivable, although the bathroom would then need to be somewhat larger as it should have a shower and ideally a cabinet. What would be less suitable in this case would be the positioning of the garage. As I said, I am a big fan of a roof terrace and there should also be a second apartment door.
Theoretically, you could also plan the garage without a roof terrace, plan the roof terrace above the garden terrace, and have a separate outside staircase as entrance to the upper floor, but here I see clear disadvantages such as extra costs, privacy, size…

I have indeed looked at such floor plans in advance and also built upon them, but there were always things that did not completely convince me, so I kept redesigning more and more.

Yes, in principle it’s of course not ideal with the laundry, but there are also many people who even take their laundry to a laundromat or who have to go many floors down to the cellar for laundry in a multi-family house. However, I would probably also plan a separate connection on the upper floor so that a washing machine could stand there.

Listening is apparently not your strong suit? You seem to feel the need to argue any nonsensical answer.

Just take with you what is important to you. Otherwise, you should think about why the experts here are signing off.

Here is one more truly well-meant piece of advice from me regarding the many really good hints. Educate yourself about building regulations, planning guidelines, learn to read and evaluate development plans. Only then buy your plot of land. Of course, you can also ask the experts here for help. But in that case, it is always better not to come across as a know-it-all.

If you then want to DIY plan your floor plans (you are not the first here), we can think about it again.

Sorry for the eye strain. But you can see yourself that your plan really is not good.

I’ll save us both the lengthy criticism.

No, I will not allow myself to be portrayed here as a “little dumb” child. And those who have signed off were the ones who themselves could not handle criticism of their discussion style. You can talk reasonably with me about anything, but I do not like it when it drifts into an insulting or provocative manner.

Yes, thank you, before I buy a piece of land, of course I will read up intensively on various things and additionally consult an expert. I really cannot understand your “know-it-all” comment; I never wanted to lecture anyone here on any architectural point. My only criticism was about the language style of some.

As far as I’m concerned, you can judge it as “not good,” but I do not see it as bad as some make it out to be. Of course, I am aware that the plan was made only with Inventor and an architectural program can represent things somewhat more suitably/better. However, one should still be able to recognize almost everything (or at least the points that were relevant to me).

Sorry, you really don’t understand ANYTHING. A partition wall is of course only installed when the house is being divided. Your strange sliding door with stairs in the middle of apartment 1 is not a serious attempt at apartment separation. Who is supposed to rent that?

This really achieves absolutely nothing here, you have swallowed your design whole and are in no way willing to learn. Have fun.