As especially the +7 places lately gain advantages from moving participants around and relocating them I think places back after relocation should stay in their place and not go on top of the list.
Personally, if they don’t make it to my favourites list, I don’t care if they are on top or bottom of the list 
but I guess putting them back on top just highlights that they are back as sometimes relocations take a while. However I get what you mean, some of them relocate very often so if they are doing it just to jump up the list ( which I doubt as it doesn’t make much sense) it’d be unfair to the new realms as they get pushed down the list.
i also don’t care too much as i mostly watch what is in my favorites. However, i would prefer not to list an already existing apartment on top if there are still the same people in.
How about making this list random? Maybe that would be the fairest solution to all. So, everyone will be on top and on the bottom of the list sometime no matter if relocated, names changed or new!?
There doesn’t seem to be any consistency.
For example Artem returned after 2 months away & he’s down near the bottom of the list. Karolina returned after a few months away and she was put to the top of the list.
(I voted for no btw)
I think that the apartment should remain in the same position as when the participants left.