1 big house or 3 small houses?

5 meters wide, floor space index not considered. In short: Forget it!

And what about a house group (three terraced houses)? They would then even be relatively wide.

But they have to be built into the property, i.e., development is added, presumably at least 3 parking spaces are required. 27x9 m, if you only consider the 3m boundary distance ... those are just pipe dreams ;).

Thank you for all the answers!

The option "3 kleine Häuser" is therefore off the table.

So the question remains whether 3 townhouses or one house with 3 separate floors. Does it now depend only on personal taste, or are there also objective arguments?

Parking spaces are not a must-have.

First, check with the building authority to see what's possible or look into the development plan. Building 3 full floors could definitely be rejected...

Parking spaces are not a must have.

Maybe not for you, but the development plan usually says otherwise.