250000€ gross construction costs for a single-family house in southern Baden-Württemberg

... @moderators ... the post by the architect could be pinned somewhere.

That's what I call a friendly "better leave it"...

I realize that 250,000€ is very tight to impossible. But 450,000€ for a simple house without any frills? So no automation, smart home, etc.? That can't be right.

Without calculating, usually around 100,000 are added.

That is a statement I would not fully endorse in its generality. Almost 50% additional costs do not come out of nowhere, especially if you have to watch the money.

a simple house without frills?

Have a chat with . He built under comparable conditions. However, in SH.

I realize that €250,000 is very tight to impossible. But €450,000 for a simple house without frills? So no automation, smart home, etc.? That can't be.

Oh yes... And you also have a hillside location. All-in, we are also planning (without land) more than €450,000 - and that's without hillside location, without a basement, without automation, without smart home, without photovoltaics). But in addition to the pure house, of course, the ancillary building costs (including connections, etc.) are included. And that's in a significantly "cheaper" region than southern BW. If you only apply (in my view too low) €2000/m2 and consider the additional costs (including hillside location), you will definitely come to >€400,000. And that WITHOUT luxury.

But you don't need a simple house without any frills. The slope demands something special. Groundwater requires a white bathtub. That’s already two frills and still nothing achieved.

Read again what the well-meaning architect wrote to you. It does not say that you don't need an architect-designed house. It says that even in the simplest case you have to calculate above-average costs per sqm. Estimates towards 400k are completely appropriate.