Too bad, you might have caught someone who really knows their stuff and would build everything exactly to your wishes (and more things you haven't even thought of yet), and you let the opportunity slip away. Others in the forum, on the other hand, are constantly looking for something like this. Just some thoughts...
Hello Mycraft,
I ultimately decided to go with the KNX option. Together with the electrician, I adjusted the hardware again to our needs, so now I have landed at just under €13,000. I think everyone can live with that now.
There is still the possibility to do the programming yourself. That means the basic settings are done by the electrician, and the fine-tuning after an introduction is then done by me personally.
This will reduce the effort costs again, which are currently still included in the offer "depending on effort."
I think it has become a fair compromise.