Hello,
I have just received approval from my housing cooperative to build a privacy screen on our patio.

No issues with this, but a problem that has arisen is how we should anchor the privacy screen itself.
My initial plan was to use ground anchors and as a second option concrete piers, but after the board consulted our builder, it turned out there is a waterproof membrane for the garage relatively shallow under our patio, and therefore we cannot use either of the methods.
That's why I'm turning to you in this forum here and wondering if you have any good suggestions on how I should anchor my privacy screen. As you can see from the pictures, I already have a partition wall with the neighbor that stands stable. I'm also not allowed to remove stones or drill into the existing paving.
I have considered a solution where I bend an iron plate into a U and weld a post base on top, which I then wedge over the curb stone and then hope that it's enough to attach it to the partition wall?
I am open to all suggestions! Thanks in advance.