From your description, I don't see any need in feeding the Black Kite. Yes, its partner might be nesting and the Black Kite is looking for more food. But the Kite is able to find food itself. If the Kite has been there for a few weeks, that means there are plenty of food. Otherwise the Kite would fly to other sites and won't stay there. Please note that the territory of a raptor is not restricted to an estate.
Unless it is injured, we do not encourage to feed wild birds. If you feed the kite, it will rely on your feeding and it will lose its ability to find food in the wild.
Trust the nature and trust the kite, it can survive in the urban area!