Bedroom in the basement

Hello,
we are looking at a plot of land tomorrow and I am already actively planning whether it even fits our expectations. The problem is that it is very narrow and therefore only a house width of about 8m is possible. I can’t manage a reasonable upper floor where the bedroom, dressing room, master bathroom, children's bathroom, and 3 children's rooms fit. Then I had the idea to move the parents' rooms to the basement. We want to build that anyway.
Does anyone have experience with living or even bedrooms in the basement? I think that in a new building, it can be designed quite well so that there is no basement feel. And we would mainly be sleeping down there. The only disadvantage I see at the moment is that you have two flights of stairs to the children's rooms, which wouldn’t be a problem forever.
What are your opinions on this?

Does anyone have experience with living rooms or even bedrooms in the basement? I think that in new construction you can design it quite well so that it doesn't feel like a basement. And we would mainly be sleeping down there.

The latter is said by the one who wants three children's rooms

What your state building code says about living spaces in your federal state is important: sufficient lighting, ventilation, second escape route on the floor, room height, heatable...
Certainly, you can sleep in a basement room that lacks all of this, but it would not be permitted or comfortable. Illnesses creep up slowly; many/everything here has its reason.

The latter is said by the one who wants three children's rooms

Good argument! But it has nothing to do with us... I briefly skimmed the HBO, it says 2.20m and 1/8 of the floor area as window. The basement is definitely supposed to be officially developed as living space, with heating etc. In terms of price, I think it shouldn't make much of a difference, since the basement is planned anyway and the heating will just be on a different floor, as well as the controlled residential ventilation, etc.

The basement is definitely supposed to be officially converted into living space, with heating, etc.

Great!

Play around with the rooms a bit. Where would the office be?
Do you have a slope? Would it be an option to use the basement as the living level, the ground floor as the children's level, and upstairs the bedroom?

You could set up the office (on the ground or upper floor) as an emergency sleeping place. The marital bed plays a smaller role here.
Joking aside: how old are the children?
Usually, the concern is more with the parents not being close enough to the children, rather than the other way around.

Bedroom in the basement is a really bad idea. You can't get the climate under control there. Too cold in winter (walls), too humid in summer. Also too dark and uncomfortable.

I had it for years in a [Souterrain Wohnung], where the basement was even exposed, and still sleeping was anything but pleasant.

I can really only advise you not to do it.

You won’t get the climate under control there. Too cold in winter (walls), too humid in summer. Also too dark and uncomfortable.

I actually can’t imagine that in a new build basement with heating and controlled residential ventilation? Darkness is not a problem since it’s a bedroom. At the moment we have it 100% darkened 24/7 because we only use it for sleeping. The blinds are also down in the dressing room so no one can look in. That’s why I don’t see much difference compared to rooms in the basement.