Apart from the actual question; you want to move in together in the shared house for the first time? I hope you know each other very well.
That was also one of my first thoughts ...
Otherwise, the salary is of course not bad, but not a real big hit either. The same applies to the house planning; the big success will not be achieved that way.
Starting a family tears a big hole in the finances, not only during parental leave but also in the following years.
We have two children, bought a terraced house AFTER the birth, I believe we would have dared more without the children. Today we are happy because the house fits the financing perfectly. The family income is around 4500,- (working time 100% to 60 - 70%), we hardly had to restrict ourselves and the financing runs comfortably with an acceptable installment as a full repayment loan over 20 years.
this year there was 1 week of winter vacation, 1 week Transalp with the racing bike and 2 weeks summer vacation. I have to rethink that
That’s always easy to say. But leisure activities are important, work-life balance is a topic. Family vacations during school holidays cost a lot and you should be able to offer that to the kids. My own "adventures," similar to your Transalp trip, also cost money and without them I would miss a lot. The woman also has to get out sometimes ...
Your girlfriend is of course right, if others manage it, you can too. But at what price? I have colleagues in higher pay grades who live only for their (admittedly very nice) house. That wouldn’t be for me.
Regards from northern Berlin