Whether one wants to take on a 400k financing with an income of about 4000 net afterwards? I don’t know
I actually don’t find it problematic at that age.
It’s similar for us, with the difference that we are both civil servants. Our first child is just about to arrive.
Of course, you’ll have to tighten the belt a bit until the second child is old enough for the wife to go back to part-time work – but after that, depending on the interest rate conditions, it shouldn’t be a problem.