Assessment of financial feasibility and expected conditions

You write that due to the 100% financing the interest rates will be high.

95 / 90 / 80 / 60; below that it rarely gets cheaper.

But that also depends a bit on the bank. Some partners like insurance companies usually don’t go over 80/90. That’s why it’s easiest to survey the market with a broker; they can also quite easily calculate with less or more equity.

Don't worry, that would be okay as is. However, I would still find out when the heating and windows need to be done. I don't know the house and the location, of course, but for an old building with "a bit of modernization in the early 2000s," I find the price quite high for the Ruhr area. Is there really no room for negotiation on the price? With houses from the 50s, I am personally always a bit skeptical about the quality of the building materials used after the war, but that doesn't always have to be the case.

Google the site baufi24 and then go to mortgage interest rates. Then you will get a pretty good impression.

50% - up to <80% almost the same
From 80% there are interest surcharges.
Whether this is linear now probably depends on the bank's model.

A higher repayment rate also leads to a lower interest rate.

I find Jean-Marc's point still very relevant.
Not that in 1-2 years the building fabric does not turn out to be so good after all and an additional 100K€ is needed because a new heating system, windows, and a roof become necessary.
Maybe an independent expert wouldn't hurt.

Question about the purchase price of the house. Doesn't something need to be done there? We have never viewed a property without immediately having a handful of points to add to the list...

Doesn't something have to be done there?

I think so too. The last renovation was already 20 years ago. I wouldn't postpone that with "sometime." It's best to do something like that before moving in, especially if it’s going to be renovated anyway. Once you've moved in and, for example, want to lay new network cables... you move furniture back and forth, tear everything up, and everything takes twice as long.

I have now played around a bit with the calculator on the Baufi24 page and the difference between 100/95/90 is marginal... but of course, we will need to get detailed advice from a bank or an intermediary again. Due to the high interest rates, a mixed financing with a KFW loan would certainly be interesting.

We will have the property inspected by an expert again, but we haven’t seen anything that we would want to change based solely on our wishes/tastes/comfort preferences. The two bathrooms are really modern, with stylish ceramics and a walk-in shower. Throughout the house (except the bedrooms) there are nice tiles, the floor plan on the ground floor is open, there is a nice fireplace, a sauna in the garden, a small pool in the garden and so on and so forth... we really don’t have high expectations and would be more than satisfied with it. We are satisfied with our current 1960s high-rise rental apartment as well, it’s just that the garden is missing and the neighbors upstairs can be annoying sometimes :-)

Of course, things look different when it comes to things that need to be done because their service life is coming to an end. However, network cables certainly don’t count among them. As I said, the windows are old and should definitely be replaced in terms of energy efficiency. The same applies to the gas heating system. The roof still looked good but of course, an expert has to verify that again. Apart from that, I wouldn’t know what other renovations should be due. The electrical and sanitary installation is 20 years old and should therefore still hold up. What could certainly also be considered are further measures for energy optimization, but is it worthwhile? The house has a clinker brick facade, I would have to educate myself on whether something like that can be insulated somehow without completely tearing it down or not... In my eyes, the poor energy efficiency is the only noticeable drawback.

Thanks for all your answers and good suggestions!