....
Including phase 1 is optimal,
but if you think about it,
Phase 2-3-4,
they can be automated by robots.
Or remote controlled from here on Earth.
But including phase 1 with people,
will be a whole lot faster.
Have robots build the city?
Then have people go in there?
It is a process for machines after all.
(Phase 2-3-4) Even 1, but that is for people.