Site planning on a gentle slope with filling

doesn't the street have a curb? The street is not allowed to drain onto your property. The neighbor certainly not.

Ignoring the costs for now, it doesn’t hurt that the house sits slightly above street level.

Plan a path to get into the garden with a trailer. At some point, there will be huge amounts of hedge clippings and so on. Heavy things have to be transported repeatedly.

I would maybe leave 1 meter of space by the terrace and then retain the 2 m (OKF 479 - natural level approx. 477). Not build the wall in one piece, but in 3 steps that can be planted. It looks better, smaller walls - L-shaped stones are easier to handle. Then at about 466.5 a small wall and then let it taper off. There is not much slope left there.

You can also set the house 6m away from the street and then make a path up to the house. It can also overcome a height difference of 1.2m or more.

I repeat my question once again.

How much does it cost you to deliver and install 1 m3 of load-bearing fill material?

You need about 500 m3 according to your design. That is 50 trucks.

180 m3 less if you plan at street level.

For the lowered house, only the soil replacement (max. 100 m3).

Now you can calculate for yourself whether you prefer to create a gutter up by the street, in case there is no curb.

The street itself has a longitudinal slope.

Sandbags are nonsense; that was planned incorrectly. You can see it in the photos. It makes my hair stand on end when I see the leveled plots.

You can also place the house 6m away from the street and then create a path up to the house. It can also overcome a height difference of 1.2m and more.

The building application has been submitted. In my opinion, hardly any changes to the floor plan are still sensible. But they are strictly necessary. The height was at least not specified in the section.

I would have built more with the slope as well. The OP decided against it.
Although a lot is supposed to be done in self-help and with a somewhat more skillful layout than in the proposal, it can be really nice and even affordable.

By the way, the plot is completely flat compared to our plot.

I think we will limit ourselves to graveling and rough modeling for now, adding natural stone to slopes or slight terrain changes might still be possible later with a mini excavator. At the end, outside the plot, there is a 3m green strip that may only be used as a meadow; I would have to clarify if it might later be allowed as a mini excavator access path.

does the street not have a curb? The street must not drain onto your property at all. The neighbor definitely not.

The street (still) doesn’t have a curb, whether one will ever be installed.. I don’t know, 1-2 plots are still free :D

I’ll repeat my question.

How much does it cost you to deliver and install 1m3 of load-bearing fill material?

You need about 500 m3 with your design. That's 50 truckloads.

180 m3 less if you plan at street level

For the lower-lying house, only soil replacement (max. 100m3)

Now you can calculate yourself whether you prefer to create a channel at the street, if there is no curb.

The street itself has a longitudinal slope.

Sandbags are nonsense, that was planned wrong. You can see it in the photos. My hair stands on end when I see the leveled plots.

The frost protection gravel is coming at a friendly price, I don’t have the exact amount yet, I’m calculating 20€/ton including freight. I would have estimated 700 tons for my design, which is probably too much.

I definitely wanted to avoid the sandbags. The savings from 180 m³ less would of course be nice to have, but the channel at the street would have to be very pronounced. Unfortunately, a lot of water came down there.