I created the thread back then and had the following done by Poland:
~30m2 terrace (including approx. 3.5x4.5m roof)
~50m2 wooden carport (approx. 9x5.5m, so just below the threshold for requiring a permit)
~75m2 driveway/path paving
In the end, the terrace became 10m2 larger, and the paving was 15m2 more. In addition, a small wall was added, but the fence construction was dropped (I did that myself).
After 2 years, I would like to share my experiences, but despite sending the affidavit + contract documents (which are required here), I received a warning and my report was deleted. Does anyone know who I can contact?
Short summary: For the next house, I will have everything done by German craftsmen.