Can we afford this? Income / Investment / Equity

and in 3-4 years it will start... as soon as interest rates rise and prices fall, strike

And this is also gambling. Of course, interest rates can rise. But who says

You seem to have quite a functioning crystal ball. Congratulations on that.

To the actual question here:
Yes, you have good conditions to afford building a house.

Income is good and equity capital is also well available. Just also develop scenarios regarding income fluctuations with offspring.

We had already saved €250,000 in equity capital by our mid-30s, which we invested in the house construction. Generalizations like the above are simply nonsense. You can also build equity capital without inheritance. For example, in our case:
Good income, low expenses and thus a monthly savings rate of €2,500. That way we were able to build up the equity capital in about 8 years.

Good luck to the thread starters.