KfW 40+ and 10,000 Houses Program - Requirements for Photovoltaics?

Thank you for the quick response! With 218m² usable space and one residential unit, I would then come to 2680 KWh/a. Unfortunately, I am not very familiar with DIN V 18599. Is it possible to make an estimate of the order of magnitude for the kWp the system would need to be sized? It is a gable roof with a 35° pitch, unshaded southeast orientation (approx. -30°) in Hamburg. I once read that 1 kWp is about 1000 KWh/a, so the offered 4.68 kWp seems somewhat oversized to me.

But smaller than 4kWp also makes no economic sense.