Cost coverage for fencing that is not desired

And here we have the neighborhood dispute. Woe if the concrete wedge from the curbstones is on the wrong property.

And now we have a neighborhood dispute. Woe betide if the concrete wedge of the curbstones sits on the wrong property.

No, we don't have a dispute. As I said, he can do whatever he wants on his property, and that's exactly what he's done. So for me, the matter is settled.
However, the concrete wedges of his curbstones are actually about 15-20 cm on our property. But I don't care, soil will go on top and the root probably won't be disturbed.
But just out of interest, how would it be if I wanted to put up a fence there myself? You can't just remove the wedges... as I said, we had considered putting up a privacy screen about 3-4 m by the house, but now it will at least be different than we thought. Could you drill into the concrete wedge for fixation?

The concrete wedges of his curbstones are actually about 15-20 cm on our property. But I don’t care, dirt will be put on top and the root probably won’t be disturbed.

I also felt disturbed by this matter-of-factness or thought to myself that one simply doesn’t do this without asking. Meanwhile, it’s out of my head and doesn’t bother me. However, I still maintain that I basically find this intrusive and that it should be addressed in good time if the neighbor will be affected in any way.
That’s my wishful thinking in social interaction. I think that will quickly pass for you as well.

But just out of interest, how would it be if I wanted to put up a fence there myself? You can’t simply remove the wedges... as I said, we had considered putting up a privacy screen about 3-4 m near the house, that will at least be different than expected now. Could you drill into the concrete wedge for fixation?

With that, you can tie courts up for years through several instances, wasting time and money. Provided it was the only suitable option, I would of course drill into a concrete block located on my property. The question is rather to what extent you can “use” the neighbor’s pushing ahead for yourself without annoying him. He has now built a fence, which is not a disadvantage for you; I would consider the underground concrete wedges there irrelevant. I think there are many options that do not disadvantage either side or open a new can of worms.
If needed, post a picture and more ideas will come.

And here we have the neighborhood dispute. Woe betide if the concrete wedge from the curbstones sits on the wrong property.

You might find that funny, but for me it actually happened that the neighbor's workers wanted to dump a 40x40cm thick slab for the fence posts onto my property. I just caught it in time and explained with hands and feet that I was okay with 10, 15cm above ground level, but not a 40x40 large concrete puddle, just because he didn't feel like setting up formwork and had dug the hole way too big... If it's agreed upon, okay, no problem. But if no one asks me beforehand, then no concrete wedge goes on my property, not even a millimeter.

I also felt that way, that this matter-of-course attitude bothered me or I thought that you just don’t do that without asking. In the meantime, it’s out of my head and doesn’t affect me. But I still maintain that I fundamentally find it intrusive and that it should be addressed in good time if the neighbor will be affected in any way.
That’s my wishful thinking about social interaction. I think that this feeling will pass quickly for you too.

Yes, that’s what I think too. I would have liked it if it had been addressed in good time, but oh well. Maybe he was also "angry" that he couldn’t enforce his plan to cover the costs and skipped the conversation about the concrete on our property. Who knows... but honestly, by now I don’t really care anymore. But the action certainly leaves a bad taste...

You can tie up courts for years through several instances and waste time and money. If it was the only suitable option, I would of course drill into a concrete block on my property. The question is more to what extent you can "use" the neighbor’s advance without upsetting him. He has now built a fence, which is no disadvantage for you; I would consider the underground concrete wedges there as irrelevant. I think there are many options that don’t disadvantage either side or open a new can of worms.
If needed, post a picture and then more ideas will come.

It’s not worth it and I’m not thinking of building a fence in front of it now. The money will be invested in great plants instead of gray concrete and a fence :) And as you say, I enjoy my property boundaries anyway that will happen eventually and the concrete wedges probably won’t bother my plants. We’ll see the rest next spring when we set up the garden.
I was just basically interested out of curiosity whether this is permissible.

If needed, just upload a picture and then more ideas will come.

This is how it looks right now. Our L-shaped stones are 280 cm away from the house.