Ground charge ordering - notary contract, ground charge...

She is always seen as the fool as long as she does not own half (land register).

Not really. She is also not listed in the loan agreement.

Later she will of course be registered, but at the moment, with an income of €400 as a student, I do not want to oblige her to sign a loan. How do you see the down payment? Thirty percent seemed like a lot to me without much in return. But apparently, that is the standard.

The topic has already been discussed x times here. At the moment, that may be the case because it brings in little or no money. Usually, even in equal partnerships, it still happens that the woman, through her labor at home (taking care of the children), enables the man to earn the money. This should be equally honored through appropriate ownership arrangements. I am a man btw. Anyway, that was not really the question here.

Find the down payment also very high. However, I am not an expert in that.

For the 30%, there is the Auflassungsvormerkung. Thus, the property is secured. The 30% roughly corresponds to the property value, slightly less. I am just afraid that due to the recalculation of the standard of living because of the two people and the net income not yet adjusted, the loan will turn out much worse.

For the 30%, there is the priority notice of conveyance. This secures the property. The 30% roughly corresponds to the value of the property, slightly less. I'm just afraid that due to the recalculation of the standard of living because of the two people and the not yet adjusted net income, the loan will turn out much worse.

A bank salesperson can also see that you can adjust your net income to around 3700 euros due to the change in tax class.

So what would the installment be then? Let's say 1500 euros, that's perfectly fine. No bank will claim otherwise.

The down payment on the property will of course be credited to you as equity. Have you even talked to a bank yet? I would first go to the house bank, explain everything (marriage, tax class change, equity, etc.) and then use these conditions as a reference – optimizing through further comparisons is always possible!

Especially if you want to be at the notary in October, I would tackle this quickly.