Financing a single-family home solidly?

90% definitely want a special repayment and are willing to accept bad interest rates for it, and 90% do not use it in the first 10 years. If the 200k€ was saved up yourselves, you have already proven that you can live frugally. I also see no problem.

Ok great, one more question about the interest rate, we already had a conversation with a financing advisor. In rough calculations, we came to about 1.3% for a 20-year term. Do you think there is room for improvement or is this a good interest rate for the current situation?

I've never been in so much debt in my life

You are not going into debt. You are investing money from the bank in real assets. Overall, your asset/liability situation does not change at all.
Many only see the large loans. But the fact that there is also a long-term stable real asset (and not a consumer good) on the other side is often overlooked.

Could you perhaps say something more about the interest rate? Do you think there’s still room there? Thanks!

Come for a quick check. 550k with 150k equity on 400k loan and repayment 2.5% (12xx€) 20 years at interest rate of 1.33% kfw cannot currently be included due to restructuring.

If you manage to reduce the loan to 385k, you will have "only" 70% loan-to-value, which is even better than <80%.

Yes, it’s self-saved. Although not much happened in the first 2-3 years after the child. In the last few years, we were able to do quite a bit.

Well, we don’t know your lifestyle and previous saving rate. But if a large part of the 200,000 was saved in the last 3-4 years, you must be living extremely frugally. With 4,800 net... Honestly, the relatively low repayment surprises me. 5k extra repayment per year isn’t that much either.

But overall, it all fits.

I have zero fear of our almost 500k loan either. I just pay it every month like I would normally pay rent. I never calculated my rent for the next 20-30 years either.