110% financing in one or two loans?

I feel sick about the €300 installment. So every month this high amount for nothing and again nothing...

Why do you feel sick about the €300 (additional) installment? If we – hypothetically – were financing €400,000 and had to pay €2,000 monthly with a net income of €3,000, I could understand that, but like this?
For example, I am getting a salary increase of €250 net monthly in January – with that the installment is almost no longer noticeable. I know you think much more conservatively than I do, but this is really completely manageable, especially since the timeframe is manageable.

And that’s actually the problem: they are over 30 and haven’t managed to save the purchase incidental costs and have now tied themselves to an extra €300 for the house loan.

Those €15,000 are not really an achievement, that should be covered twice by the VWL plus a few euros.

But to really judge this properly, more info is missing.

That is not a problem, because we have calculated everything multiple times down to the last detail and know that we can (well) manage it.

Additional info:
We met late and used to have other priorities and lifestyles.
For example, nice cars were important to me, which I always paid for in cash. Because of that, I burned through an extreme amount of money, I am, of course, aware of that and I regret it in hindsight. But I simply can’t undo that now. Meanwhile, cars don’t matter to me at all. I know this is often doubted skeptically here in the forum, but: Opinions and attitudes change. In the future, due to the location of the house – on the edge of the forest and yet only a 15-minute walk to work – I won’t need a car at all anymore, which means that selling them will also bring in a few thousand euros.

My boyfriend has been an orphan for 17 years. In other words, everything “normal people” got over the years in “subsidies” (even if it was just rent-free living until moving out) from their parents etc., he never had. Since he was 17, there was no one who paid for his driving license, his first car, or even rent and groceries. Not to mention gifts at Christmas or birthdays. His parents also left him nothing, meaning he was completely alone as a student (!) had to provide everything himself and couldn’t save anything for a long time.

Then you have to consider that the rent for our 2-room apartment is already about €1,000. I don’t want to imagine where rent might be in 25 years, whereas our loan installment will then be about €400 (and our incomes will be higher by then as well).

The mentioned building savings contract is obviously not the only one; there are two more, but they will only mature later. Additionally, there are other insurances, retirement contracts, etc.
By the way, the advance notice from my employer amounts to a crazy €6. The soon-to-mature building savings contract being discussed was saved without advance notice by me.

And as I've mentioned several times, with the current price increases in real estate, you simply can no longer save your way to the goal. In the end, we would have saved €40,000 next year, for example (as mentioned, we currently also have equity but are using it differently), but then we wouldn’t find any house below €250,000 – what would we have gained? We could say we saved the purchase incidental costs, yay, but the loan requirement would still be higher than it is now.
Especially since the house we found is simply the perfect property for us, both in terms of equipment and location. We wouldn’t have found anything like that anymore, I’m 95% sure of that.

Wise statement that shows a clear plan and determination. It makes one believe that even without a high equity ratio, there is enough substance behind it.

I say this, whose aversion to consumer loans is probably well known. That will not change either.

You can't sugarcoat the 110% financing for the total costs, but I don't see a €245k loan as critical with two full earners. Sure, it's a shame about the money paid to the bank in interest at the beginning. But not buying now because of that amount and first saving up for additional costs is unnecessary and very likely a zero-sum game. If it were a loan over €450k, that would be a different matter.