Duplex or two-family house?

But that would really be the pain threshold. In the end, I don't want to leave a mountain of debt to my daughter (who is still very young now).

That is a totally wrong thought. YOU are building for YOURSELF and not for your daughter. And apart from that point, you are not leaving a mountain of debt. You are usually leaving value-stable assets in the form of a house. Whether the daughter inherits €100k debt and €150k house value or €1.5 million debt and €2 million house value doesn't matter. The assets exceed the value. The large numbers should not scare you (and your death should not be your advisor either).

A mortgage is usually backed by a corresponding value. It’s not like the money was spent on short-lived consumption (a world trip or similar). I also have a loan, but I also have the house, which is worth more than the debt. So I have net assets.

For the planned project, existing properties are certainly not available in abundance. An apartment for six people, plus commercial space...

Yes, that is correct. However, since we are not bound by time or location, we will find one or the other property. We have already looked now and then, but just for fun. There were already some interesting and affordable properties within a 20km radius. I am really optimistic about it.

Make sure that these are not dilapidated houses. Affordable currently means massive renovation backlog. I don't believe that those who bought the property and then carried out extensive renovations got a better deal.

Quite possible. New would of course be my preference, as I said, but at these prices, because we have a corresponding need for size. A "normal" new single-family house would be no problem for us price-wise. But then there isn’t enough left for the rest. It’s not easy, but I’m not driving myself crazy at the moment, I’m just absorbing information so that I’m mentally prepared.

Affordable currently means enormous backlog of renovations.

The search term "divorce lawyer" leads to three posts of mine - from my Barthel series with tips on finding real estate: ## ##