Building a house - building savings contract with bad interest rates

I am certainly a fan of tight financing when the framework is right and the details are calculated precisely.

But here I also say: hands off or slim down by at least 100,000 euros (better 150,000 euros).

that sounds like troll mail or personal bankruptcy

Thank you for responding at least partially seriously. Of course, without family support it would be totally naive. That is why I am asking for advice. It's not about being put down - no, thank you - but rather about realistic tips and help on how much we should approximately still save or borrow from family (or receive as an early inheritance gift)...

A gift is one thing, but borrowed money must also be paid back. Are the parents/in-laws wealthy enough to be able to provide such a large amount of money (interest-free)?

There is the question: what does "so viel" mean? How much do I realistically need from you? Quite a bit of money is already with my parents, grandparents, and an aunt of my husband - yes. The question is whether they will leave it to us. Definitely interest-free, they would only come up with the idea of wanting something for it.

200-250K€ gifted and not loaned. Then it might fit.