So 10% of the construction sum seems about right, I think. You have a bit more area and overall many more tapping points. But yes, I have now requested a meeting first. My goal would either be that he convinces his subcontractor to still carry out the design and the installation plan of my MEP planner, even at additional cost from my side (although I don't believe it, since that was exactly the reason for his withdrawal) or that he hands over to me a specification sheet for the trade with a stamp, so that it is absolutely clear what the new plumber now has to do and what will be done by the subcontractors of the main contractor. Ideally, of course, I would prefer that he finds another subcontractor who simply does what the old one was supposed to do and that's that. But I think that's the least likely. Thanks for your information. I am building in Berlin, my preliminary inquiries have already resulted in two companies that have basically shown interest, whether they will be able and willing remains to be seen—regardless of the price...