What kinds of locks must be on the front and rear doors of my building?
The front and rear entrance doors to the building should each have a DEADLOCKING LATCH, which automatically locks when you shut the door. From the outside, it can be opened only with a key. From the inside, it can be opened merely by turning a knob or handle.

If my building has a vestibule or lobby, with an outside door and an inside door, must they both have a deadlocking latch?
No. Only one of these doors must have this latch.