(1) For the ISS, Habitable Volume is: 13,696 cubic feet, and Pressurized Volume is: 32,333 cubic feet
(2) For the BFR, the ship volume is: 38,400 cubic feet (all habitable).
This means that a single BFR ship, placed in orbit, exceeds the total volume of the the ISS by a significant amount. So putting up an entire space station can be done with a single BFR launch (assuming the BFR ship is tasked as a space station).
It also means that placing a single BFR ship in lunar orbit immediately gives a space station larger than the ISS in lunar orbit (assuming the BFR ship is tasked as a space station).
A single BFR ship landed on the moon immediately becomes the initial lunar colony.