House purchase from the year of construction 2014 with 118 sqm living area and basement

Well, that sounds good. I'm keeping my fingers crossed that everything works out and that in a few years you can say: "Alles richtig gemacht."

In case of doubt, it will just be sold again. We certainly won't be unhappy about that. Even if the common expectation at the moment seems to be at least 20sqm per room for some. We would like that too, but I don't want to pay for it.

I also think the offer is good and you save money, trouble, and uncertainty. Have fun in your new home!

Congratulations on the decision!

Even though the common expectation at the moment seems to be at least 20sqm per room for some

You can have many expectations, but when I walk through the current new development areas, the "~120sqm category" is by no means extinct. You even have the basement, so it's no problem at all.

Good decision!
I would have taken it too in your place.
Perfect location is much more important and also more permanent than compact rooms.
Expansion potential is also there, but bigger is not automatically better.
Office in the basement works great, playroom in winter too, in summer you’re outside anyway.
Hope everything works out and you move in soon and will be happy.
P.S. is the bathroom really furnished as in the floor plan?
It wouldn’t be a deal breaker for me, but clever is something else.

What do you mean by furnished? There is a bathtub and the shower inside as shown.