Floor plan of a single-family house with approximately 150 sqm on a rear lot

Do I understand that correctly? Then the planner probably did not use a survey plan. Even in the Geoportal, you can map the property better. The corner at the neighbor's garage is not 90 degrees.

You probably don't want to back out of the property, that will make it difficult to maneuver.

Well, as a first idea maybe still quite okay. But why are you planning your cabin yourselves? That’s what architects are for.

Regarding the details: The L-shape of the living area might be a wish, but you sacrifice terrace access, light, and view from the kitchen. It’s not worth it! Here I would look for other design options or simply insert a wall if necessary.
A simple terrace door is narrow and uninviting. It should be a double door in the new building. The glass sliding door for the kitchen is supposed to be the one running in the wall? I’m wondering if I’ve ever seen such a thing? Does it even exist?

The laundry tower upstairs is, in my opinion, nonsense – the headroom by the stairs will be too tight because of it. The bathroom is too tiny and very poor for a family in a new building. I would be annoyed about that forever. Even your guest bathroom is bigger.

The second bedroom for the parents is very cramped and resembles a closet. The first one, because of the space used, is not really great either. I’m in favor of large children’s rooms but here the proportion is off.

Conclusion: List space requirements and budget and go to the architect without a sketch.

Am I understanding this correctly? Then the planner probably did not use a survey plan. Even on the Geoportal you can get the property more accurately. The corner at the neighbor's garage is not 90 degrees.

You probably won't want to reverse out of the property; that would make turning around difficult.

Yes, correct. The plan so far is that we share the driveway with plot number 190/25 and also pave it together. This way, the driveway up to the neighbor's garage can also be used for turning around.

Well, as a first idea maybe still okay. But why are you planning your own house? That's what architects are for.

So far, no willing architect found in Nuremberg-Erlangen-Fürth. Planning a single-family house apparently is not in demand.

Regarding the details: The L-shape of the open-plan room may be a wish, but you are sacrificing terrace access, light, and the view from the kitchen for it. It's not worth it! Here I would look for other design options or, if necessary, just insert a wall.

So far we find the open-plan room in a narrow shape unattractive. Do you have examples for separation by room dividers, kitchen islands, or walls?

A simple terrace door is narrow and uninviting. It should definitely be a double door in a new building.

The door itself is 1m wide. Do you mean the door is too narrow or that the door at the existing width should be divided into two sections?

Should the glass sliding door for the kitchen be recessed into the wall? I'm just wondering if I've ever seen such a thing? Does it even exist?

Actually, we have not planned it as recessed into the wall.

The laundry tower upstairs is, in my opinion, nonsense – the headroom at the stairs will be too tight because of it. The bathroom is too tiny and very inadequate for a family in a new building. I would be annoyed about that forever. Even your guest bathroom is bigger.

The bathroom on the ground floor has the bathtub and no pre-wall, but actually, the rooms are almost the same size. So far we found new bathrooms too big. In the end, they are rooms where you spend only a few minutes.

The second bedroom for the parents is very tight and resembles a closet. The first one is not exactly great either due to the space used. I am also in favor of large children's rooms, but here the ratio no longer fits.

In our previous rented apartments, the bedrooms weren't bigger either. They should simply provide space for a bed and a wardrobe. For bedroom 1 we planned a dormer/gable instead of a roof window. The children's rooms are intended as sleeping/play and study rooms, so we imagined this size.

The glass sliding door for the kitchen is supposed to be the in-wall sliding one? I'm just wondering if I've ever seen one like that? Do they even exist?

Yes, we have one - although made of frosted glass between the living room and kitchen.
Built-in, 2 wall sections each about 12 cm including plaster and about 3 cm in between for guiding the glass panel. So a total of about 27 cm "wall thickness." I suppose with drywall construction it could be narrower.

I would really rethink the property division. I am a big fan of the west side myself, but if there is a boundary garage 3m away, it would certainly be worth considering attaching your own garage there as well. How many parking spaces do you have to create, or need?