Hi guys.
Yes, I know many will probably think I'm "stupid" now, but hopefully many will still be able to understand.
We have decided NOT to buy the house.
The problem is that it's not just 430k, but overall we're talking about 470k, plus the "wet wall" that could come back, a very ultra tight budget, two-colored wood on the house and so on and so forth. Oh yes, and a bathroom with which you would be "living" for almost half a million. Also the problem with the heating etc. There are way too many reasons against it.
Then there's flickering in the basement and on the first floor regarding the lighting, or it sometimes goes out briefly, then comes back on and it's not the bulb. Furthermore, the wet wall was apparently opened back then because there was a short circuit and I suspect there is still an electrical fault in the house. And on top of that, it was unheated for three years. That's not so nice either.
The conversation with the bank advisor was also very enlightening...
I could have barely gotten a loan from my house bank as well, and it would have been paid off before retirement, but even the bank advisor ultimately advised against it due to the low equity. (monthly payment would of course have been catastrophic)
In the end, I sleep much more peacefully and am glad that I don't have this "problem" now.
In our community, it happens more often that a house is sold and, ultimately, my eyes have now been opened that I will now save a lot more money and keep a household budget.
The topic house or property is by no means off the table - but now I will work towards it for a few years first and not make a drastic life decision under pressure within a week.
The other couple will surely be happy now, but they have a completely different starting position from the ground floor.
In any case, many thanks to everyone who actively contributed here and gave advice.