Can a landlord actually have 5 apartments on one electrical outlet box

This is a function of local building codes, not real estate law.

can a landlord actually have 5 apartments on one electrical outlet boxDepends on how the electric is billed.
If there is only one meter it is not uncommon for the electric to be included in the rent.

There is almost 100% chance that he cannot legally sub-meter the electric. If the electric is charged separately there must be one meter for every space PLUS one for the LL and common area loads.

Unicorn_love - IM surpriozed that it ever passed inspection, aroun here if it was tried , IT WOULD NEVER HAVE THE POWER LINES HOOKED UP TP THE METER!! I would feel like I was living in a FIRE TRAP IF IT WERE ME < TAlk to the power co in your local, BUT NOT TO THE LADY IN FRONT <ASK TO SEE ONE OF THE ENGINEERS> HEERS hoping you stay safe GOD BLESS < :::F.B.E>