Building a house without equity - is that possible?

Seriously guys, you are party poopers! Nothing is better than youthful exuberance.

I think you should just go through with it. I have been looking for an attractive house in the foreclosure auction forever. I’m happy to wait another 2-4 years.

At the best house-building age, the OP even had enough time after the private insolvency to build equity and make a second attempt. Easy!

I do believe that the banks will play along with you. But you have to go there yourselves.

But honestly: start living.
What's the point of a house if you do nothing in it or on the property except doing nothing?
Nowadays, a house or apartment, besides providing protection, is meant to develop your personality. Somehow, you seem to be struggling with that. No interest in life, just possession.
No interest, no hobby. And if a passion should arise, there’s no money for it.
Another problem: as planned, you can't afford a child for now.
And at some point, you get on each other's nerves. Reading this already makes me tense, that’s why I appreciate my hobbies - over 50.
I don’t envy you, your wishes are childish, but at the moment you earn money like adults. That’s tempting. But it doesn’t lead to smart decisions.

Wow, it couldn't have been written better, chapeau!

Sorry, I forgot (I intentionally deleted all quotes because everything was said by others)

Save up first for ownership in the area of vehicles.
Just because you are "at the source, meaning: the automotive industry" does not mean that comfortable leasing or car financing is the way to own something.
An own saved-up car is, in my opinion, the first consumer-relevant footprint in a person's life. Then it can go on.
In principle, you have achieved nothing yet. At work you are beginners, you have created nothing, you own nothing except a few pieces of furniture and your clothes, and you reach for the stars. But there are still some steps in between that should be taken. Further education is already a good choice.
Everything else cannot be used for personal success in the long term.

Somehow I can't put this situation together. 19&20, finished the apprenticeship, i.e. started at 16/17. BU each 50€ (starter version or too little coverage)? But then a relatively expensive UV (hazard group B, craftsmen?) What do you do for a living? The distance learning is free (new to me or is it further training disguised as a degree?)? The great thing after an apprenticeship is the sudden lot of money. Unfortunately, you get used to it very quickly... if someone had offered me 2000€ net during my studies, I would have quit and gone there. That was 4 years ago. 4 years ago that was an amazing salary for me. Today, with 3k net, I wonder where all the money goes and the 15k bonus is already allocated... What I want to say has already been said by almost everyone.