How does everyone afford a house?

In the end, I believe it’s a matter of priorities and attitude – do I eat the 8 euro special in the canteen or "settle" for the noodles for 3 euros and be happy that I saved 5 euros. For one person, one makes them happy, for another the other. To save 100,000 euros in 10 years, you don’t have to earn super well – good is enough, I think. For example, we save 65%, 16% rent, 5% car, 7% food, 7% other (I’ve offset kindergarten neutrally with the child benefit). Again, it’s the same topic: on the outskirts of town or in the city center.

We both bring food from home, only go out to eat on special occasions or to the bathing/sauna paradise. We don't need the daily newspaper or Bild newspaper. We simply don't need all that. We pay attention to offers when shopping... The children don't have to or rarely have to do without anything (you simply can't have everything.) But over the years, quite a lot added up, so that we were able to put in more than 1/3 equity. And on the subject of location: we are building a large, very well-equipped single-family house on a large plot of land in the countryside in Northern Baden. My relatives got an "average" small terraced house on a small plot near Heidelberg or in the Munich metropolitan area for the same money. Everyone has their own priorities.

Huuuuuundred euros? I don’t exactly consider our life a life of luxury now. ...
You’re kind of scaring me. Somehow it all sounds like “living at the minimum or paying rent forever.” ...

That might be the small difference why some can afford a house and others with more income cannot: Some cycle through the countryside with their family on Sundays—completely free—and have a romantic picnic. Others have to entertain themselves for a daily rate of around €40/day and go out to eat afterwards.
The cyclist on the picnic meadow experiences life as a luxury at that very moment, and you don’t, even though you spend hundreds every day.
It’s all a matter of attitude!

And somewhere between constant expensive entertainment and living at the minimum, there is still a good middle ground—I and my husband belong to the category who have less than €50 in phone costs by the way—Huuundred euros? ... I was really surprised when I read that from you. In my opinion, the relationship to the euro is missing if you talk on the phone for 100 of them!
(I originally had a smiley here, but instead I put an exclamation mark)
Life is certainly not miserable if you don’t spend even €100 at the cathedral, play soccer instead of taking piano lessons, and prefer to arrange a romantic evening at home instead of a wellness day outside. Please don’t misunderstand: we could if we wanted to! But for example, it gives us no satisfaction to just open our wallets until there’s nothing left at the end of the month.

As with milkie, it's the same with us. I prepare my own food at the office or take leftovers from dinner, my wife eats at home anyway. We also don't go out to eat often, but vegetarian dishes in restaurants are often boring, so it's not worth it. I'm no longer at the stadium every weekend like before, but significantly less. My sport is affordable (longboarding), my boss pays for my commute, etc. In addition, we didn't pay rent for a few years. This allowed us to save a decent amount with our 4,500 euros net (now 4,800 euros) and pay for the land itself (including additional costs 135,000 euros) and still have almost 80,000 euros left, with which kitchen, moving, further additional costs, furniture, etc. are paid and an emergency fund is formed. For this, we also moved out of the city, where the plots are significantly more expensive. However, I don't have a longer commute because of this, so we don't get worse off there.

Apart from that, as an example: I pay a total of €15 for myself and my wife for two mobile landline flat rates, two mobile internet flat rates (1GB high speed then throttled), and we call each other for free. How does one get to 100 euros there? We never went out to eat regularly (which is also boring and personally doesn't add value to my life), on the contrary, you can also host a cooking event at home with inexpensive means (maybe with a few friends), which personally gives me more "back".

It's not that difficult Iphone 6 for rent and Telekom tariff and you're already at 70 €... but again: if it brings joy, why not.