Zinspoker - Long term or short term?

50,000 € is actually also the amount the energy consultant calculated for us for façade insulation with hemp (his recommendation) as well as the new windows.

Sorry, but I have to bring you back to reality. For a building of this size, it will be impossible to get both items at that price. I speak from experience. Windows will not cost less than €30,000 unless there are almost no windows/patio doors/front doors.
Standard providers quoted me around €30,000-35,000 for a 200 sqm house (with many small dormer windows) for materials and installation (no additional work etc.) about 1.5 years ago. Today it will not be cheaper.
And I am doing the façade insulation myself now. The material alone costs a five-figure sum (sic!). And that as the second choice! Plus scaffolding, plus labor.

Sorry, but I have to bring you back down to earth. With a cabin of this size, it will be impossible to get both positions done at that price. I speak from experience. Windows won’t be less than T€ 30, unless there are almost no windows/patio door/front door. 08/15 providers quoted me about T€ 30-35 for material and installation (no finishing work etc.) for a 200 sqm house (with many small dormer windows) about 1.5 years ago. Today it will not be any cheaper. And I’m doing the facade insulation myself now. Just the material costs a five-figure sum (sic!). And that as second choice! Plus scaffolding, plus labor.

I have two offers in front of me, called last week, arrived by email this morning: Windows €26,889, Facade €29,500 Sum: €56,389

But after spending almost all of my free time in model home parks in 2019, I can't shake the feeling.

A model home park is by definition sterile. Like a hotel too. But that doesn't necessarily have anything to do with one's own house.

Nonsense, you can still buy oil heating until 2026 and after that also as a hybrid system.
Gas has just now been declared a green bridging technology, there are no bans.

True, the ban from '24 was overturned because it was not feasible. But that does not mean it won't come back.

So you probably don't have much to fear from renovation obligations. They certainly do not apply to occupied buildings, but only at the next sale. Or with the new heating system.

If the government wants to achieve its goals, there must also be an obligation in existing buildings, and not only on change of ownership. A comprehensive renovation when installing a new heating system is certainly a viable approach. But that also means that as an owner you will eventually face a spontaneous major renovation.

And by the way, this was not about the question of to what extent the house should be renovated, how energy prices will develop, and whether it is better to build new, but whether I pay off the place all at once in 12-15 years or pay it off slowly.

For your question, after the payment, the topic of renovation is usually essential. Even the average higher earners in your income range don’t just have money lying around to pay for major renovations like switching to a heat pump out of pocket every few years. I think with your switch to 2% amortization you are exactly right financially. Anything that is paid off in about 30 years by calculation is quite good, the main thing is to be finished before retirement and not your original 50 years (1% amortization). Whether you then make extra repayments or not is of no importance.

I have two offers in front of me, called last week, landed in my inbox this morning via email: Windows €26,889, Facade €29,500 Total: €56,389

If that’s so cheap, then order it immediately! It’s like a gift.

The question is just what was requested...

If the government wants to achieve its goals, a requirement must also be introduced for existing properties, and not only upon a change of ownership. A comprehensive renovation with a new heating system is certainly a feasible approach. But that also means that as an owner, you might suddenly face a major renovation at some point.

That would be a consistent expropriation through the back door. I don’t know how it is where you are, but where we are, 80% of all properties date back to the 50s and 60s. These are largely still in their original condition. They are inhabited by people who work or have worked in the local industrial companies. 5-10% are newly built properties from recent years, inhabited by higher earners, and at most another 5-10% are renovated old properties. People live in unrenovated old houses for good reason – because they cannot afford to modernize them.