My home financing 2025 is bursting against reality

I’d rather leave the money in the daily savings account, I get triple the return, no work at all with it, and have access to it at any time.

Some people just hold on to their property. It was the same with Telekom shares back then: many didn’t even realize they were going downhill and held on to them just because they had been high once.
But: I can’t understand it either.

These will not be 50m² studio apartments, but rather around 20-25m².

Put in a few pieces of furniture and you can rent them out for 450€-550€ cold. At least in the metropolises and university cities. We always see apartments between 20 and 30€/sqm.

Most of it has already been mentioned here, but something fundamental. You are living completely beyond your means. You have gotten used to a standard of living that is not sustainable. With just under €5,000 net, you go on vacation four times a year, eat out every weekend, probably order food occasionally during the week. Then you also live in an expensive area, your rent is probably not the cheapest right now. Since your wife apparently has a different opinion about this, or you have worked through this whole process with yourself, you first need to align yourselves. It makes no sense for you to restrict yourself, dream of the house, and your wife to have completely different goals. Of course, it is rare that both partners share 100% of the same dreams and opinions, but at least the partner must want to support the decision. If she only does it for you in the end, then it is not sustainable.

Then you also live in an expensive area, your rent probably isn't the cheapest right now.

Free of charge in one of the mini-apartments with 25 sqm. And that including a child. I don't call that "living," but "cramming."

Nevertheless, it is defended, allegedly. By someone who demands a high standard? I maintain that stories that are too strange to be true are usually not entirely true. And something here is very strange.

Free of charge in one of the mini-apartments with 25sqm. And that includes a child.
I don’t call that "living," but "housing."

You can’t be serious? You can’t properly settle in like that, develop economical routines, and create a nice everyday life. With a child and wife on 25sqm, I would also go on vacation four times a year and eat out. How else? There’s not much cooking or living going on there. I totally understand the wife. With so little quality of life at home, everything around it is naturally even more important to her. Otherwise, she has nothing.
I’m not saying that this is terrible if it has to be this way sometimes. We were poor too and sometimes lived as three in such a small space (mom, sister & me). That really bonds you together, but in the long run, it’s not sustainable. Especially not when the child gets older. That’s not good for the relationship or the child.

But of course, this is difficult now. Either rent a bigger apartment and "give away" money to a landlord or buy. With a bigger apartment, you’d also have to adjust your lifestyle, but you’d gain a lot more quality of life at home. At the end of the day, though, there is no realistic option for you to save a lot more.

What you need first is a long conversation together to plan your future.