Building a house at 21 years old .. too young?

I don't find the floor plan so bad either. The hallway does indeed get a bit tight if jackets and shoes are supposed to hang there. You might have to improvise a bit. However, I don't understand this bay window thing. It costs an disproportionate amount of money, and instead, the house could be a bit more spacious. For the bay window money plus a little extra, I would rather extend the wall of the kitchen and living area to the same height as the bay window. Then the bay window is gone, but the entire house is bigger. Downstairs, you would have more space in the living area, and upstairs you could make the bathroom a little smaller and then place a storage room between the bedroom and bathroom. Additionally, the children's rooms would be a bit bigger.

That has deficits, is not uninhabitable and not small. There have been much worse usable proposals.

First of all, it is a house for 2 with more than enough space and it can also fit 4.
I would still properly draw in the open plan room. It could be tight.

Our north bedroom has its advantages at temperatures beyond 30, in the winter half-year it is much darker than the children's room next door.

The OP now just has to come up with clever detailed solutions for points that the floor plan itself does not optimally solve.

It is just annoying and expensive: if you come to the homebuilder now with extras like a drawer under the stairs, it costs. Even doing it yourself. And yes: a house has a roof over your head and keeps you warm, it is habitable and above all makes you proud and happy. You only curse it later when many residents, meaning with children and strollers, don’t know where to put stuff and junk. In my opinion, it is too expensive to plan everything based on the experience of people.

That may all be true, but it can no longer be changed now. So the OP has to adapt to the circumstances.

can't be changed now.

I just saw that the OP was here only two hours ago - a comment wouldn't have hurt to find out if we are really now hypothetically philosophizing about the emperor's beard. In that case, I really hope he can still bring in the tip about dividing the stair underneath space.

Of course, things could be nicer, but when I see the houses of my relatives, almost everything about this floor plan is an improvement over the existing buildings. Still, no one is unhappy

I personally have no doubt that with the floor plan (despite the undisputed deficiencies) you get a house where you can live wonderfully with clever use of space. Even with 2 kids.

100% agreement. People, the house builder is 21 years old. That is an age when you are very flexible and have no problems fetching shoes from the utility room or elsewhere. I also don’t think that at that age you have already accumulated 8 jackets for 4 seasons per person and that they all have to hang there. At that age, I had one jacket for summer and one for winter. That’s enough. Somewhere a hook on the wall or door... done. As you get older you become very narrow-minded and you all provide the best examples of that here. Everything MUST be perfect, everything else is a total disaster...? Are you even aware of that? By the way, my hallway is under 2m². Behind it, there is either a staircase going up or down. Still, there is a stroller standing there. Is that a problem? No!