In any case, I prefer to spend my time above ground rather than underground.
Yes, me too. I generally find basements always uncomfortable, whether in my parents' "old" 70s house or in new buildings. Basements are simply not my thing, not even when they are converted into living spaces. Almost all the rooms that builders often put in their basements would not appeal to me there. Apart from whether you really need a party room, hobby room, home cinema room, or whatever at all. In our case, these rooms would probably stand empty permanently because they wouldn’t be used, whether in the basement or above ground. But of course, this is different for everyone, and there are certainly people who enjoy that, and for them a basement is more suitable than, for example, in our case, especially when land prices are steep.
Just for storage, a basement would have been too expensive for us. Therefore, it was immediately clear to us that we would build without a basement. Here in the countryside, land is still very affordable (€55/m²), so in case of doubt, we would rather build larger above ground than with a basement. But I think we have enough storage space as is — more is always nicer, but you really have to ask yourself whether you need it. I see it with my parents: a huge fully basemented house. Plus a garage with a workshop. And the basement is packed to the last corner. But if you look at what my parents actually use and need… you could throw away about 90% of the stuff. But because they have the space, everything is simply kept. There are still school notebooks from my elementary school days stored there that will certainly never be looked at again, and old carnival costumes from 1980 that no one will ever wear again.
In our house, we will have a utility room with just over 10 m² on the ground floor (technical equipment, washing machine/dryer, and, for example, some shelves for rarely used kitchen appliances, etc.), a storage room under the stairs of about 4-5 m² (for, e.g., cleaning supplies, drink crates), a storage room behind the garage with 18 m² (e.g., for tools, bicycles, lawnmower, possibly garden furniture), the attic (gable roof) for rarely used things like spare tiles/paint, seasonal decorations, discarded children's toys, etc., and a large walk-in closet with about 7 meters of wardrobe space where all our adult clothes will be stored along with bed linens, sportswear, etc. In addition, we also have a study where all paperwork will be stored and, if necessary, things like a yoga mat can be stored there if there is no more space in the utility room. I think we will manage with that. Would we have really needed a basement just for storage?! I don’t think so.
By the way, very few builders in this region build with a basement. Estimated maybe 10%, if that. And we live in the countryside, where people have "always built with a basement," and most plots also have a (slight) slope.