Unrenovated single-family house from 1973 - Renovation or new construction?

Thank you for your answers so far!

And thank you for the cost estimate, Joedreck. What I listed above is by no means comprehensive. These were only supposed to be the things that wouldn’t also be needed in a new build. It would need windows and a roof as well, so with your estimated values that would total 55k. I think at least the facade insulation will be more expensive; the architect estimates 35k. But even then, we are still far from the costs of a shell construction including demolition. The floor plan changes (yes, I was unclear there) are nothing major: moving a door and making an opening between the kitchen and living room.

And for T€ 270 renovation you get EVERYTHING you can imagine. Including golden fixtures. Awesome! I would have guessed €1,000 - €1,200 per sqm - all in.

Well, not exactly gold but that's true. Roughly €1,500/m² plus a safety margin for unforeseen expenses. And you should be on the safe side. For the necessary trades, you can get quotes. Then you know what’s possible in your region and have cost certainty. I would skip the architect. Look for a civil engineer to supervise the construction support.

Roughly 1500/m² + a safety amount for unforeseen expenses.

I consider that clearly too high for the size of the house (160 sqm). The larger the house, the lower the cost per sqm. My professionals usually start at 1,000€ for gutting – which then results in new-build quality.

I know. It should rather provide the feeling of security that 270k is too high. But still good to know that one can...

I am currently carrying out a very extensive renovation. My list says that I will end up at around €1500/m² ready to move in. But that includes everything, including floors, lamps, and the kitchen. The garden will come later.

My professionals usually start at €1000 for a gutting – that then reaches new build quality.

What exactly do you mean by "my professionals"? If you run it commercially, it will presumably only be calculated as turnkey. I could have also done my renovation project turnkey for €1000/m² without the new dormers and done more simply (for example, insulation in EPS instead of mineral wool).

Anyway, I would find the cost breakdown by trade from the architects much more meaningful than all the incomparable case examples. : Can you post the list here? Then we can also give better feedback.

Addendum: According to the Living Space Ordinance, I have approximately 150m², according to DIN 277 a net floor area of 200m². If I had divided my figures by the 200, the price per square meter of the renovation would look correspondingly better.