Should the land be filled up or not?

I understood it so that the original poster wants an effective driveway width in the sense of the width between the house and the fence of 3.50 m available, and the general contractor now wants to use 1.50 m width for the terrain modeling area – so the planned width is to be inflated to 5.00 m in order to end up with 3.50 m usable width after deducting the unexpected width requirement of 1.50 m.

I see it the same way. But the property owner does not seem to want that.

You have quite significant earthworks to carry out. With my suggestion, the mass balance should almost work out. Starting from a 1 m height difference in the building area, a basement should already pay off.

We only have 10cm of topsoil, so the earthworks will probably not be as extensive as expected.

According to the person who prepared the soil report, we have perfect soil conditions.

It is the terrain modeling that makes it complicated.

I understood it so that the OP wants an effective driveway width in terms of the width between house and fence of 3.50 m, and the general contractor now wants to use 1.50 m width for the terrain modeling area – so the planned width should be inflated to 5.00 m in order to subtract the unexpected 1.50 m width requirement and still end up with 3.50 m usable width.

Yes, that’s exactly how he explained it.

And my question is, do we really have to assume 1.50 m for that?

That’s how I see it too. But the property owner doesn’t seem to want that.

We do want a well usable driveway and, if possible, to get 2 cars on the property because there are already parking problems there. But to be honest, I’m no longer sure whether it was even a requirement for us to have 2 parking spaces.

But do I really have to sacrifice 1.50 m for the L-walls?

A basement/living cellar/integrated garage should cost 70-100k, that was and is clearly above our budget!

You can't look at it so generally.
It doesn't just simply come on top.

Terrain modeling, retaining walls, paved driveway, no garage/carport, smaller floor area, etc. all change the price.

I would recalculate the idea of the living cellar and integrated garage more precisely.

If it ends up costing 15-20,000 more, but in return you gain "more space," this could be an option.

You can't look at it so generally. That definitely doesn't just come on top. Terrain modeling, L-stones, paved driveway, no garage/carport, smaller footprint, etc. all change the price. I would recalculate the idea of the basement living area and the integrated garage more precisely. If it ends up costing 15-20,000 more but you gain "more space" in return, this could be an option here.

We initially had 3 regional general contractors who were closer to our consideration. All 3 ultimately quoted an additional cost between 70-100k for the basement/garage situation. If it had been 15-20k, we also wouldn't have said no.

We initially had 3 regional general contractors who were considered closer to us. All 3 ended up quoting an additional price between 70-100k for the cellar/garage situation. If it had been 15-20k, we wouldn’t have said no either.

As I said, of course when the question comes up "How much does our planned house cost if we want to add a cellar?" I understand the additional cost. But if you relate living space to usable auxiliary space right from the start on a hillside plot, it quickly relativizes. A slab foundation on a hillside is not much cheaper. It was basically only meant as a food for thought. The usual "That costs at least 100k€ more" cannot be generally applied like that. Example for us: 165m² living space including 70m² auxiliary space - we could build with a cellar, eliminating a lot of the auxiliary space and gross floor area. But it doesn’t actually pay off for us because we would have to plan a waterproof cellar and that again disrupts the cost/benefit ratio. There was even a thread once where the cellar was only partly made of concrete and the front living area was made of solid wood.

As I said, of course the question came up "How much does our planned house cost if we want to add a basement?"

It was more like we discussed our ideas at the beginning.

Then the question about a basement came up. And we said we wanted a basement (which isn’t true, actually we didn’t want one), but it’s easier to leave it out afterwards than to have it planned in again.

Then there were standard floor plans and the approximate prices for the house according to the construction service description, once with a basement where the house had just under 130 sqm and once without a basement, house about 170 sqm.

And then the price differences and how much of that difference is related to our land and our ideas.

So with the cheapest general contractor it came out to something around 72k and with the most expensive about 97k.

But to be honest, I can’t even say exactly what was taken into account. It’s already a bit over 1.5 years ago.

I will call the managing director of the general contractor again on Monday, I had the building meeting with him too.

Let’s see how he sees it, he also advised us very well during the building meeting.