Is financing feasible? Single-family house 155 sqm

One more question: Where do I have to go for this jump? Taking parental leave with A13 is of course a luxury. Would it be conceivable to repay more in the first 6-7 years as long as you both work full time? The repayment switch was actually always offered to us, no matter which bank. Maybe just ask again if something is possible.

I personally find the financing requirement quite high for your income, but not impossible.

You are in the advantageous position of still being young and currently having no children, so you can actually save well in the first few years and make special repayments, so that in the case of having children, the rate can be reduced until the girlfriend earns again.

Personally, I would look for a financing bank that offers a repayment change! I have never received an offer that did not include at least 2 changes. You should specifically inquire about this with your current offer!

And otherwise, see where you might make compromises (house size, double garage, etc. etc.) depending on what is planned to make the whole thing a bit cheaper.

Why is parental leave with A13 considered a luxury? My wife is A10 and receives the highest rate. Whether she becomes A11 or A12 beforehand is therefore irrelevant.

Salary-wise, it would definitely be feasible, or we could pay the installments relatively easily, but you are always forced to go to work to be able to afford a little something.

Of course, it makes no difference for parental allowance (see my first answer), but it apparently does make a difference for any part-time work.
As an example: A10 with level 3 and 50%, tax class 4 is about 1,500, with A13 we are already at 2,000 (in Bavaria). That is a huge difference.

But that is a general luxury of the pay grade and has nothing to do with parental leave

It doesn't matter anyway. The installments are affordable but make a substantial amount. If you can sleep well with that, then go ahead. For me, that would be too much financial commitment over too long a period, but I'm not the one who has to pay it.

I see all of this as unproblematic: good salary, equity saved, enough buffer, house costs realistically estimated, thoughts about parental leave made. Everything fits.