Build all required parking spaces, even if they are not needed?

It is also questionable whether the 30,000 € actually represent a buyout, or if one additionally has to build a parking space afterwards.

Here is a sketch. The architect says he is sure that the green garages and parking spaces will be accepted. But he has little hope for the yellow ones (only the bottom right). The only alternative from his point of view is a duplex garage instead of the garage and keeping the green parking space.

If you don't really need the two yellow parking spaces, in place of the area marked at the bottom right, I would simply designate two parking spaces and secure them with plastic grass grids. If no one is constantly driving on them, grass will grow over them and they will become invisible. If you plan a fence, just put a manual gate there and that's it. It doesn't cost anywhere near €30k (or €60k if both yellow ones are under consideration) and should meet the requirements without much effort or creating an unsightly appearance.

The duplex garage from the sketch by is approximately 4m high. Thus, it is not allowed at the limit. I claim that it is simply not possible to create 6 accessible parking spaces on the property. How about the floor area ratio? That must also be exceptionally high for the project. Whose idea are the two semi-detached houses anyway? To me, this looks like a single-family house plot that is being pushed to its maximum.

If I were in the place of the area marked at the bottom right, I would simply designate two parking spaces

So far, we have little hope that the building authority will approve the parking space at the bottom right, as it requires a second entrance from the main road.

By the way, the duplex garage from the sketch by @Benutzer200 is just under 4m high.

It would work underground.

I claim that simply no 6 drivable parking spaces can be created on the property.

It certainly is not easy. I hope it is still possible.

What about the floor area ratio? That must be exceptionally high for the project.

The floor area ratio was not defined in the old development plan. The development plan is no longer valid and the entire area, including this property, has a very high development density.

I assume that you are at least doing a notional division according to WEG instead of an actual division.

The driveway will most likely be WEG-divided. The houses and the surrounding gardens will be actually divided.

Even with three parking spaces (I read the number as an indication of two residential units per semi-detached house), it is common to have only one access road.

This is a general rule for any residential unit larger than 100 sqm.

From a fire safety point of view, I have doubts that it is officially allowed to squeeze through between the car and the front door.

That is another perspective. Let's hope the architect knows what he’s doing :)

If the garage is now also supposed to be partially underground, it will become even more complicated. You will then need a corresponding ramp, for which there is no space either. The whole project is already very, very borderline in many respects. We are talking about a ~380m² plot, which was sold for over 2000€/m², and is to be developed with two semi-detached houses plus 6 parking spaces. Normally, anyone with some knowledge of the matter would say: completely impossible. Is there a positive preliminary building inquiry? I see a lot of trouble coming your way.