House construction financing possible in the coming years - experiences?

That was also a reason for discussion with us. We have now agreed that both of us are registered in the land register but at 30 to 70 since he contributes more equity and the main loan

Well, if you work less professionally because of child-rearing, then your partner should secure you either through an additional pension insurance or through a 50/50 share in the house. My wife and I are both 50:50 in the land register, although I had the largest share of the debt at the beginning of the financing.....

Smaller than 130m² I would actually not for 3 people

Me and all my neighbors have 122 m2 each with 1 master bedroom, 2 children's rooms and 1 office. Everything works totally well. Only the straight staircase in the middle of the house just doesn't work.

That was also a reason for discussion for us. We have now agreed that both of us will be listed in the land register but 30 to 70 because he invests more equity and the main loan

With such an arrangement, as a partner who refrains from their own employment for a longer time in favor of the other or accepts hardly recoverable loss of income, I would frankly feel taken advantage of, to put it mildly.

When taking out a joint loan for a property, where both jointly assume the same obligations towards the bank (the bank does not care at all who ultimately pays how much; that is a purely private arrangement that no one cares about in a serious case), both borrowers are listed 50:50 in the land register or the partner finances the property entirely alone in every respect. Otherwise, the project "property purchase" with such a constellation would be dead for me personally.

We have now agreed that both of us will be on the land register but 30 to 70 since he is contributing more equity and the main loan

Don't do that! You are raising your (and therefore his) children so that he can work. If he comes up with such proposals, then tell him he should take care of the children just as much as you do so that you can pursue your own employment to the same extent as he does.

That was also a topic of discussion for us. We have now agreed that both names will be on the land register but 30 to 70 since he is putting in more equity and the main loan

Higher invested equity is regulated by a private contract. For the bank, you are 50:50. 100% must be paid to the bank monthly. No matter from whom. With 30%, the ratio is not correct. You pay 50, you own 30%. In the house, after starting a family, it is fair that everything is 50/50, regardless of each person's financial contribution. With 30%, you are setting the precedent that in the worst case you will be paid out with 30%. You can then basically start anew with the kids, he sits in his house.

For the bank, you are 50:50

Actually, even 100:100! Everyone is liable for the entire loan amount.