Neighbor's concrete supports on our property

The neighbor will put up a hedge or something similar upstairs, so I don’t need any privacy screening. On the left, I might build three compost chambers, maybe some climbing plants in between, raised beds. Do you think a fruit espalier would work in that location? It is my south side, but due to the house/hedge, it is more of a shady north side.

Friesenwall ...

And once again here in the forum, we have discovered something we like but cannot afford.

And once again here in the forum we discovered something that we like but cannot afford.

Why not? Depending on where you live, you can get these large gravel stones very cheaply; I don’t know the current price per year but I once created something with them and then always picked them up in loads at our small harbor, where there were large sand depots anyway for the local construction companies. If it’s just for decoration and doesn’t have to hold anything, it might still work. It’s just a question of whether these stones are common in your area. Where there is Rhine gravel, you could ask, never in the hardware store in small bags, otherwise you’ll get poor.

And once again here in the forum we came across something we like but can't afford.

If you are motivated enough and can solve the logistical problems that such a project entails, then it is a great garden project even in EL. Just inquire about gravel pits. With us, the costs amount to about €100/ton. With one ton, you can manage about 2m³.

What characterizes a Friesenwall compared to other dry stone walls? Is it that it consists of pebbles (that is, rounder stones) or what?

And once again here in the forum we’ve come across something we like but can’t afford.

There are so many things that are ridiculously expensive to buy commercially, but if you know someone or get creative... we have sandstone in the ground, especially the houses with basements have dug up some pretty big chunks. Of course, everyone lets them be hauled away expensively, even though you could, for example, use them to landscape the garden. But nobody does that in times of gray welded wire mesh and lawn robots. Unfortunately. Nobody is interested in natural stone walls and the like.
In the countryside, you also ask the farmer if he can haul something for you and so on, the city dweller hires companies with fleets, which immediately adds a zero to the price.