What loan amount is realistic for house construction?

Expensive, I say. No, seriously, where we are, they would stone you with the property prices. A few kilometers towards the small town, where the city bus goes twice a day and there is nothing else, you can demand that in the village. Where we are, there is no city bus, but almost everything is within walking distance, you pay roughly half. I don't understand the prices. I think it's way too cheap here.

You are still young and I think it's good that you are dealing with it. I think with your savings rate, building a house is possible in 5 to 10 years.

Until then, you can also clarify the matter with your wife/girlfriend.

At the current time, as already stated several times, it is not possible and not feasible.

Even though in my opinion, solid construction with the corresponding price level for metropolitan areas predominates here in the forum.

I’ll throw a prefabricated wooden house as a shell construction into the ring. Maybe take a look towards Living Haus or Danwood and Danwood Family? Living Haus seems to be a good company.

And first turn the men’s garage playroom into a carport?

You could also plan the carport in timber frame construction so that later on you can close the walls in the finishing phase, install a door, and make a garage out of it?

On top of that, check out all the funding programs? If he builds the house alone and thereby meets the income limits, maybe glance towards housing subsidies from the state banks?

However, I still see the problem in the fact that with 160m2 of living space, certainly 2 children’s rooms are planned in the house and will still be occupied?

Maybe also consider aiming more towards 120-140m2 of living space?

What happens if those children are there and your girlfriend no longer works full-time or not at all?

Even though in my opinion the majority of construction in this forum is solid construction with the corresponding price level for metropolitan areas.

I'll throw a prefabricated wooden house as a shell into the ring. Maybe look towards Living Haus or and Danwood Family? Living Haus seems to be a good company.

And first turn the men's garage-playroom into a carport?

The carport could also be planned in timber frame so that later in an extension one could close up the walls, install a gate and turn it into a garage?

Also check all funding programs? If he builds the house alone and thus meets the income limits, maybe take a look towards housing promotion from the state banks?

However, I see the problem in the fact that with 160m2 of living space, certainly 2 children's rooms are planned in the house and furnished with occupants?

Maybe also look more towards 120-140m2 of living space?

What happens if they are children and your girlfriend no longer works full-time or not at all?

What is the question about the children supposed to mean? If he is building alone and she is not on the land register, I would expect that her salary and thus any loss of income does not matter. Then he just shouldn't reduce hours or take parental leave. You can't have everything...

Can you tell that I think the parental support issue is a pretext to keep her off the land register—but she should still help pay somehow?

What’s with the question about the children? If he builds alone and she’s not on the land register, I would expect that her salary and any loss of income wouldn’t matter. Then he just can’t reduce his hours or take parental leave. You can’t have it all...

Can you tell that I think parental support is a pretext to keep her off the land register—but she still has to pay somewhere, right?

Correct! I thought the same! And there are tons of places to get informed. We are a family of four with a gross income of 110k per year. I did a quick search. Debts on the house are actually good!

He wants, if I understood correctly, to officially or on paper for the bank, notary, mortgage, and so on only go with his net salary of 2xxx €? But he plans secretly to include his girlfriend’s salary in the form of a building savings contract and whatever else.

With his salary alone, it will fail; with both salaries, I find it tight in this range and constellation.

And what happens if children come and the woman/girlfriend only works part-time or not at all?

So first sort out the family situation, and then approach the house building a bit more modestly.