I find it hard to notice when you have added new apartments. There are no notifications or “news letter announcements” about it as far as I know.
I think you could add a filter so we can filter the one´s as “Most recently added” or
maybe even filters as “most popular apartments” or stuff like that 
It’s announced here
In most cases it is simple: the list of apartments is sorted chronologically. The newest one is always at the top, or at the top left if you are in the thumbnail view.
There are some exceptions. for example: If the residents change, but the apartment stays, then the place in the order usually doesn’t change
Okay, thanks