Cost estimate for construction costs of a semi-detached house including ancillary costs

That easily breaks the million mark for a house that is hardly more than a little cottage.

This is indeed the case in Munich and not unusual; many live like this. The question is, what alternative does the OP have? A house that is not a little cottage is affordable for very few in Munich's commuter belt.

I would at least try to find a plot of land that was not clearly divided so disadvantageously in favor of the larger half. As long as no further key data is known, it is hardly possible to sensibly discuss functionality and construction costs.

Yes, what can you say - the division is crap - exclusively in favor of the other half - the narrower plot surely also has the worse direction/location. Someone wants to subsidize their side of the house but is a very poor "giver"...

I would think twice about whether I want to play along...
GD

Serviced (district heating available) and immediately buildable [...] One contact person for the construction project "turnkey" # Implementation/ start quarter 3 in the year 2024 [...] Since the development and schedule of the neighboring property are not yet determined, we assume that the two semi-detached houses will be built separately.

Our questions:

[*] Rough cost estimate for the construction project including incidental costs (development, garden, etc.)
[*] Recommendation for a contact person, possibly an architect, to discuss the project in more detail

Is district heating only "available" or mandatory?
Your most explosive uncertainty factor is the neighbor of the other half; worst case, you differ in your stance on the basement question and also have different ideas about the house profile at the junction "shared wall side." From this, the recommendation arises to select the planner (and preferably also the civil engineer and structural engineer) together. At least the finishing can then be done separately, of course not exactly twin-like and quite possibly one wooden and the other stone-built or vice versa. Basically, I have already said all this several times; the forum search terms "Mitkellerer" / "Ohnekellerer" and "Goalkeeperthread" are your friends.

Well, what can you say – the division is rubbish – exclusively in favor of the other half – the narrower plot certainly also has the worse cardinal direction/location. Someone wants to subsidize their side of the house but is a very poor "giver"...
I would seriously consider whether I want to play along with this...

Yes, how come you already know the layout of "semi-detached house 1," but not the further planning of the neighbor?

There are barely 5.5 meters of net width left in the interior.

I have now calculated with 5.30. Over 11 meters in length (interior dimension max. 10.20), the living area without deducting the walls and stairs is 54 sqm. Side bays are not possible because of the garage, … more than 35/38 sqm for the living room is not left. But let's look at it realistically and not be negative: such terraced or semi-detached houses are a good start into ownership. Better than an apartment, the children have a small garden, and after 10 years it will be sold and built bigger. Apprenticeship years are not glory years either.

I have now calculated with 5.30. Over 11 meters in length (internal dimension max. 10.20), the living space without deduction of walls and stairs is 54 sqm. Side bay window not possible because of the garage, … more than 35/38 sqm for the open-plan room is not left. But let's look at it realistically and not be negative: such terraced houses or semi-detached houses are a good start into ownership. Better than an apartment, the children have a small garden and after 10 years it will be sold and built bigger. Apprenticeship years are not master years either.

In principle yes, but with the sums called up in Bavaria, the amount of real estate transfer tax alone spoils the fun of such plans. However, the thread starter seems to have no interest in his own question.