Build a semi-detached house alone?

This is once again absolute country bumpkin thinking (no offense intended). In the really sought-after/expensive areas, there are of course at least TWO semi-detached houses on 450m². On 900m², depending on the layout, there is a small apartment building with 6-8 units or 7-8 terraced houses. You can also stay in the city ;) a good part of Germany doesn’t laugh very loudly about that.

I know, I can relate to it. But when I see something like that, I almost get tears in my eyes.

Sometimes plots of land end up with construction companies, and then of course a semi-detached house is built there. I recently discovered our northeast neighbor on a real estate portal. The south half should still be somewhat suitable but then it’s just a mini-plot of 320 sqm. The north half only sees the sun in the evenings during high summer... by the way, it’s supposed to cost €550,000. But someone will probably be desperate enough to take it. Although I’m still curious about what will actually be built, since the house is listed in several designs ;)