2021
At the time of writing (May 2019) I wanted to see how possible a human moon landing could be made.
The key in my view would be what hardware is currently available or near completion.
We have access to LEO
Currently available
Falcon Heavy as launch
Soyuz
Working on that completion need accelerating
Bigelow Habitat
Starliner and Crew Dragon
Russian station modules such as solar power
NEEDED FAST ACCELERATION of development.
Crew Dragon repulsive landing for the moon
LEO Refueling tanker
I propose building in LEO a Luna transfer vehicle with a Bigelow Habitat module, russian Power module, two Crew Dragons with Luna landing capability, the biggest issue in my view would be to be able to fuel in LEO.