Is it possible to renovate a residential house from 1954 into an energy-efficient house? How?

According to the '54 plans at #8, I first thought: "Nice"! And the raving about the elephant seemed to bring the monument protection into the realm of possibility. But after the descriptions and the aerial photo in #17, my opinion tends more towards . The whole thing is quite built-up.
On the huge plot, there is room for a new building, and with the mixed neighboring development, the restrictions of §34 of the Building Code should be limited, or is there now a development plan? I would gradually restore the existing building to its original condition without a core renovation ('93 is not that long ago), put in a bathroom, and rent it out as a holiday home.

And the rhapsodies about the elephant seemed to bring the monument protection into the realm of possibility.

Rhapsodies, well. When it comes to monument protection, were you thinking in terms of energy saving ordinance relaxations?

But based on the descriptions and the aerial photo in #17, my opinion leans more towards . The whole thing is quite built-up.

I see it as needing a committed and renovation-experienced architect. The aerial photo makes me suspect that the roofs of the annexes have only minimally affected the statics of the core building.

So a new building is out of the question. The funds are not sufficient for that. As I said, we have our ideas, remove the veranda and continue to use the other extension. Built-in is relative, surely not everything is perfect, but on the sunny side there is enough space. We will send some photos of the current state later.

to come back to the architect’s cost plan. That thing doesn’t make any sense, right? I actually don't want to pay anything for it because it means nothing in my eyes. How do you see it?
Best regards, Sebastian

The two hourly wages are definitely even worth this, in my opinion, rather uninspired listing, even if you expected something else. It cannot replace cost estimates, and the accuracy can also still be quite low. Addition inconsistencies or an incomprehensible calculation method are also forgivable in this context.

Rhapsodies, well. When you said monument protection, did you mean in terms of Energy Saving Ordinance exemptions?

No, I didn’t think that far. You analyzed the building fabric so thoroughly and lovingly that, in my opinion, a reader from the monument authority might get the idea to put the protective hand of the state over the house. However, the aerial photo combined with the text disillusioned me.

I see it as needing an engaged and renovation-experienced architect.

That could work, but I would like to join

Relatively quickly, sums came up in our case for which others put their developer house into a new development area.

, hence my suggestion for new construction. I also see building law problems with the boundary development of the existing building. In socialism, they didn’t take property boundaries too seriously. Are all the existing extensions even approved? Yet even then the question arises whether the conversion measures are still covered by existing protection.

Actually don’t want to pay anything for it

At least he was on site, and orally some information must have been conveyed as well. I consider the 180€ reasonable. If you want to buy a property and ask a building expert for a rough assessment, you also pay a three-digit sum. But then you don’t even have anything in writing.