Of course, it would have been nice if the craftsmen had worked properly. But you know yourself, in life many things don’t go according to plan. There were also defects in my construction and also at the neighbors’. But everything was fixed by the GÜ, often without us having to report anything... even partially years after moving in... of course, there were here and there points of conflict... and you had to stand up for your rights, but often a factual discussion was enough.
So then write down everything that went wrong for you.
I have looked at the plaster strips... obviously they make no sense like that... but it is repairable since everything is still fresh... and the whole facade does not need to be redone but only the reveals.
So
1. Downpipe (repairable)
2. Plaster strips (repairable, although increased effort must be expected)
3. Tiles and expansion joints (repairable: tile out - adhesive off - cut new tile - adhesive joint profile in - new tile in)
4. Welding membranes which ones? Where? Roof, base slab?
5. Shower, here you need more information... pictures? Are there also any of the construction?
6. What else?
All of this so far is of course not great... but I would also not call it rubbish...