I think the apartment owner can give permission, but only if they've given proper notice to the tenant. Most states I believe require 24-48 hours prior notice, except in the case of an emergency. I'm not sure what would constitute a legally valid vampire-emergency, but as long as the landlord properly notifies the tenant in advance I believe they could.

Most times I've seen it, permission can be given by any resident. Ownership doesn't play a part at all. So I would guess a land lord can't give permission.

Also I recall one example of permission being required for entering an apartment, but not the building. Though in that case the vampire in question was living in annother apartment in the same building.

Do the people need to be aware their home has been foreclosed on, or can it say, be done as a legal fiction in the dead of night by a vampire corrupted bank to allow entry?

There was a 2020 documentary that elucidates this to some degree, in the sense that Vampire rules are only as effective as both the people and the vampire in question believe in them. For example, the whole burning under the daylight sun trope is merely a state of mind/habit reinforced by generations of preyed upon cultures to the degree that the vampire believes it themselves.

To this then, I say that both the vampire and the people need to be aware their home has been foreclosed on for any effect to occur.