Terraced house on a 240 sqm plot - fundamental questions / feasible?

Our requirement was that the intermediate building (garage/carport/theoretically it could have been a recreational room) must be at least 5 m wide and a maximum of 3 m high. Since your neighbor has already built like that, the 3 m will fit.

A full basement must be on the boundary where, as mentioned, the foundation of the garage stands. However, a workroom is needed at the basement wall, which then has to be created under the garage. User 11ant once wrote somewhere in relation to a semi-detached house how nonsense it is to implement that.
This was decisive for us to go for a partial basement.

Floor plans in this case are mainly for semi-detached houses or similar row houses. We did not find a suitable single-family house floor plan because the dark wall never fit, the entrance was wrong, and mainly there are hardly any floor plans with three children's rooms.
The current one is certainly not everyone’s cup of tea but covers almost all wishes. By the way, I don’t have a current view, so it no longer quite matches the current windows.

User 11ant had once written somewhere in relation to a semi-detached house what nonsense it is to implement.

My basic assessment of semi-detached houses applies here in essence as well: that this is actually a type of house for developers, or at least not a recommendable playground for first-time building owners. And what I otherwise recommend for semi-detached houses - coordination between the planners, if not a shared one - naturally applies here to the entire chain as well.

I fully agree. Both in planning and execution, a lot of money could have been saved here. However, everyone was glad to get a plot, ran straight to their preferred developers, and signed the contracts. They just didn't know any better.

erstgebärende Bauherren

That fits better than I understood at first reading.

That fits better than understood at first reading.

What did you understand there?

Both in planning and execution, one could have saved real money here.

In what way?

However, everyone was glad to get a plot of land, immediately ran to their favored builders

You mean constructioncontractors. One could not favor a builder, because only one of them owns the coveted plot of land.

Construction developers are sellers of developed plots with buildings. I meant that semi-detached houses / townhouse rows / linked houses by nature require a land developer who carries through the entire project and only sells it when it is finished (at least legally, often earlier in terms of time).

The interface "common border" sensibly remains in one hand until the entire thing can be accessed.

There are certainly opposing opinions to this view of mine, which consider this pessimism. But from my perspective, everyone working behind a curtain and only being surprised at the topping-out ceremony whether the two halves fit together is something for people who like to watch movies of the genre "Nothing is free." Personally, if I want to cry, I prefer "The Crown Years of an Empress."

What did you understand there?

I didn't know the expression like that and wanted to understand it literally.

In what way?

The interface "common border" conveniently remains in one hand until a grip can be screwed onto the whole thing.

You almost answer the question yourself and my experience confirms that. The larger quantities in negotiation and the freer execution planning are automatically reflected in the price. Whether a developer necessarily has to take that on is another question, since freedom in design is subordinate to profit.

The opposing opinions are also justified, I would proceed that way again even though the interfaces are not always transparent. In the current market situation, such risks are taken.

3. Is a 9x10m house + garage/parking space 30sqm feasible with the floor area ratio? As far as I have read, the floor area ratio may be exceeded by 50% for ancillary facilities.

Does the development plan not specify anything further in this regard? Then the Land Use Ordinance applies, as you described, provided that a version after 1990 is applicable, which, judging by the excerpt of the development plan, certainly applies here.

90sqm house < 0.4x240 + 30sqm < 0.5x0.4x240

That makes the mathematician shudder.
My suggestion:
Floor plan I (max): 240m² * 0.4 = 96m²
Floor plan II (max): 96m² * 1.5 = 144m²
For a house of 9m * 10m, that leaves 6m² for the terrace and then 48m² for garage/parking space and driveway.