What would be a reasonable maximum loan amount for us?

I personally think it’s good that you don’t want to overextend yourselves. Just as an example. We bought a condo on the ground floor as a new build for 250k and are super happy with it. Also in terms of the financial burden.

Currently, you said you would have to give up vacations, etc. I advise everyone to keep it smaller sometimes...

It has now been 4.5 years since we bought the house. Our net income has increased by "only" about 700€, as I still only work part-time and have also started my doctorate. The cost of living has increased significantly. In general, but also because the children are growing older. Soon, due to an illness, income will probably decrease.

My final conclusion: We certainly do not regret buying the house. But we are infinitely glad that we calculated so realistically back then. Today we have a household net income of about 4300€ for 4 people. When we bought the house it was around 3600€. So it is more comfortable than it was then. We can also occasionally go on an affordable vacation and don’t have to turn every cent. A broken washing machine would not make me break out in a cold sweat. We are doing well, we don’t want to complain. But a house for around 400,000€ or more would have been too much for us – even with today’s income I wouldn’t dare to do that with the current experience.
We still put a lot of money into the house every year. Into the remaining renovations. We also still have quite a bit ahead of us.

I hope this experience report can help others.

We also decided to live in a "things can happen" house rather than a house where NOTHING is allowed to happen. Maybe it's also because many people in the typical house-building age haven't yet fully experienced the catastrophes of life. At 30, you rarely attend friends' funerals, but in your mid-40s, you do.

What do you consider a realistic credit limit for us?