Designing a garden on a slope sensibly

Okay, then there is excavated material. I’ll think about what I would do – I’m putting the budget aside as well as what your development plan allows. You’ll have to check that.

Excavated material actually wouldn’t be a problem. We’re in a new development area and there’s always someone digging here.

Our development plan doesn’t really set any requirements in that regard, but I believe we’re only allowed to pile up to 1m of soil.

You turn a slight slope of about 12% into 25% and now want to know how that should be designed.

Your parents handled it quite well. Didn't they say anything about your plan?

may only, I think, pile up a maximum of 1m of soil.

Then I recommend reading the development plan again. Feel free to quote excerpts here as well. Because you cannot comply with the 1m limit with your design.

With 1 m you will have to create some terraces

The parents' property is much flatter. The OP's has quite a slope behind the house already

The development plan says nothing at all about embankments, earthworks, or anything else. It is only one page long. Does that mean we have free rein? Our parents imagined everything completely differently but would be absolutely not happy if we put a 1.50m high wall right in front of them. And I don't want that either. That's why my question is how we can best design the garden.

By the way, this is the transition to my parents. They are already overlooking an earthen embankment (which will probably be terraced). Adding another meter on top of that now would take a lot of light away from them.