How many square meters are realistic given the following financial situation?

Where did you read anything about adoption?

I have concluded:

Are children planned? Yes, we are already in the process of gathering information (as an unmarried homosexual couple, it is somewhat more difficult)

But even if other possibilities exist, I would wait for the result, since it is already known that it is difficult and one plans to build somewhat smaller anyway.
Financially, however, the basis looks fundamentally good.

Good evening everyone,

thank you for your responses and for taking the time to read everything :) We appreciate every suggestion.

The square meter number is actually also due to the desire to have children. The plan here is not to adopt, but to have our own children through a fertility clinic. Corresponding costs will still arise, as the health insurance will not cover them.

If it's within a 30km radius and not in one of the few unpopular towns, a little less, but 50K are realistic here too. If the apartment was only rented out, a (high) tax applies, but of course not for personal use...

We don't believe we live in an unpopular town, so that already sounds pretty good. We have been living in the apartment ourselves since early 2016.

but honestly, the monthly rate might be relatively high despite good equity

Can you estimate where we would land? What does "relatively high" mean?

We had already come to terms with having to reduce somewhat, but would later regret it if more could have been achieved with our possible equity of 220,000 EUR. Would you use the equity differently?

Just a different question: living with two or three people in 170 sqm is not easy either... I don't want to start a discussion here, but maybe you can come down to 140 or even 120 with a clever floor plan. That saves the most. If there is already a rough favorite floor plan, then you can work with it. Regarding financing, I would ask the Sparkasse what your penalty interest rates are and try to reduce them through the new loan.

Honestly, well-planned 140sqm is also spacious enough for a family with 2 children. Even more spacious is always nice, but not necessarily required.

I would also recommend that you calculate the whole thing with a half-day salary. KiTas do cost money, after all.

It would be good to know any wishes regarding the house design. As others have already mentioned, it is perfectly possible to live well with children in 120-140 sqm. However, if a study or one or several guest rooms are needed, or if the sauna and the roof terrace absolutely need to be planned, the above-mentioned living space will be very tight.