Positioning of the house on a small plot (again)

Garage north under the garbage area, house rather elongated with gable east-west, southern orientation of the main windows as well as photovoltaics facing south. Classic

Elongated along the street.. Ultimately, you would then have a small, west-facing garden, then two meters from the property boundary, then the neighbor's garage (3.50m?), and then the 9.30m high house, which because of the eaves height of 4.50m might not seem as overwhelming as a city villa.. I am especially somewhat worried about sitting on the terrace and feeling crushed by a stone wall.

The south-facing windows would ideally look over the new bungalow development. To the north, on the other side of the street, there is so far only greenery / gardens of the 1.2-hectare existing properties. To the west, one could still orient dwarf gables toward the garden.

.. and: what should the house be able to do? One should go by that. What kind of needs are there? For whom? Is a simple garage enough? Are 2 parking spaces needed?

A simple parking space with a bike shed behind it is completely sufficient. 2 parking spaces are not necessary, there are permanent parking options for visitors / cars of older children directly in front of the new development area.
3 children, everything can be small..

The south-facing windows would overlook the new bungalow, ideally. To the north, on the other side of the street, there is only green / garden of the 1.2-hectare existing plots so far. To the west, one could still orient dwarf gables towards the garden.

.. and: what should the house be able to do? You should base it on that. What is the need? For whom? Is a simple garage enough? Are 2 parking spaces needed?

Simple parking space with a bicycle shed behind it is completely sufficient. 2 parking spaces are not necessary, permanent parking options for visitors / older children's cars immediately in front of the new development area. 3 children, everything can be small..

Lengthwise along the street..

No!

Ultimately, one would then have a small, west-facing garden,

No, I was talking about the south

No! No, I was talking about the south

then you would lose a lot of garden square meters to the north through the garage in the north and the rubbish bin storage area located even further north, and you would only have garden strips/green strips around the house, right? The house would then be practically in the middle.

then you would lose very many square meters of garden to the north through the garage in the north and the garbage bin storage area located even further north

To be honest, I can't follow you.
On the one hand, anyone, especially someone with a family of five, can certainly use an area that is apparently "over" by 3 meters in width for personal garbage/compost, children's fleet of bikes, laundry area, second seating area, or raised bed.
So you don't lose anything at all, but rather gain an advantageous spot that is naturally shielded from the rest. Besides, this area also extends to the west. In addition, open space at the house ensures that daylight comes into the house through a window or patio door there.

The house would then be practically in the middle.

Yes, that's great. Not a duplex on the property boundary, but a house in the middle of your own property.

Would only have garden strips/green strips all around the house, right?

Or not? I don't get it: I said narrow house. With 18.25 minus 3 meters for carport/garage/parking space, you have 15.25 left. With a house width of 8 or 9 meters, you have 6 or 7 meters of garden left. To the west, the building area is defined anyway, the neighboring house is tall. And that's then "green strip" for you?
If that's the case, then you won't be happy with this property.
I prefer a bungalow next to my garden. Then you can see the sky. It is your choice to build differently. But you asked.
However, if I were you, I would put more thought into a suitable house: three children's rooms are rarely offered and do not exactly make house planning easy. That would be my focus if I were in your position, and then see if or how you can set the house well. But you mostly get the light into the place from the south.