Mezuzah Eligibility

Question

In follow up to Bob's question and your answer below: 1) If I am a rental tenant in an apartment building, what is the size of the room/closet in order to require a mezuzah? 2) I have a mezuzah on my front door. That door opens into a corridor about 2 or 3 feet wide and about 6 or 8 feet long, which then opens into a large foyer. That last opening has no doorpost or moldings, as the wall just opens outward. Does that opening need a mezuzah? 3) In between my living room and bedroom is a small area, about 3 ft x 3 ft large, with 4 doorposts. One leaves the living room, one enters the bedroom, one enters a walk in closet (about 4 ft by 4 ft, and one enters a bathroom. Does this small area need a mezuzah on the opening from the living room, or on the opening into the bedroom, or both? Thanks for your time! Max ------------