...The nice thing about her is that she at least tries to understand the other opinion, something that not many here in the forum always manage, all the more something I appreciate about her. ...
Everyone has the right to live however they like. My opinion. But a forum is also sometimes there to wake someone up, to straighten things out, to show reality when you notice that someone has a wrong perception. As a forum member, you have to live with that: me as well as others.
If someone here states a salary of €6500 for 2 people, that is more than if a couple here states €4000. If the savings rate for the latter is €1500, it could be €4000 for the former. Other factors left aside. If someone wants to build, you suggest €4000 to them. What they make of it and what they can do with it is another matter entirely. But hopefully, you have set a thought process in motion.
I once looked on IS24 (Munich area 30 km): it really is a small catastrophe, the lack of real building plots. But there seems to be a policy behind it, because there apparently is enough housing to buy. It is known that I am a fan of used houses. At some point (with the second child) you can sell them again and change. That is of course easier when the real estate price is generally lower (because of the purchase incidental costs).
4000... for some the savings rate, for others the total salary - this number as such should simply show someone what might be possible for them. The more equity saved, the easier it is later, the more choice you have.
I have read envy and mainstream twice in this thread. I do not have the feeling that there are people here who envy the OP or that the OP has fallen for the mainstream. Personally, I certainly do not find this situation great: qualified and good salary, but you have to really “row” in the economy to get through what you want. Life is sometimes actually easier when you work for less in the village - it is not a less beautiful life, and you are not a worse or less knowledgeable person because of that.