There was a paper by Craig Davidson (presented by Zubrin) on why a lunar base is better than the proposed Lunar Orbital Platform-Gateway (LOP-G) to advance human space exploration.
The Lunar Gateway would be a Mir sized space station in orbit around the moon. If there is a requirement to go to the Gateway before going to the moon then it would add a 30% cargo penalty to sending missions to the surface of the moon.
It would take four launches of the unbuilt Space Launch System or the unbuilt SpaceX Super Heavy Starship to build the Lunar Gateway. It could also be built with 20 Falcon 9 launches or the equivalent of twenty space shuttle launches.
The opportunity cost of the Lunar Gateway is twenty different interplanetary missions.
There are resources on the moon. There is ice in the permanently shadowed regions of the moon and there could be ice elsewhere under one meter of soil. The average temperature of the moons extreme temperatures is -50 degrees. The average temperatures is what exists below one meter.
Rocket fuel can be made on the moon. Either hydrogen-oxygen can both be produced by electrolyzing the water or methane can be brought and lunar oxygen can be used. If methane is brought using lunar oxygen saves 80% of the mass. Methane is the fuel for the SpaceX Super Heavy Starship and methane is easier to handle as a rocket fuel.
Getting the Lunar Water
The problem with the ice is that it is in shadowed craters. If we have new Kilopower nuclear reactors we can put the reactor inside the crater. If we are using solar power, then the solar power has to be at the sunlit area at the top outside of the crater. A microwave transmitter and your trans beaming power a few kilometers into the crater and then you have a tent which is transparent on one side aluminized on the other. The microwaves reflect back from the side of the tent and down into the ground alternatively the tent could be entirely transparent. You could just have a reflective dish behind.
The general idea is to microwaves tuned to heat water. Microwaves will penetrate into the ground and water ice will be vaporized. It will come out as steam. This is particularly attractive if the water is the in the form of a permafrost where it’s mixed with dirt.
The permafrost of moon craters will be an extremely strong and hard material. It would be too hard for Pickaxes. This is the reason for microwaves. Water vapor will be captured and put into a trailer tank.
You do not want to be hauling batteries into the crater to try to vaporize ice. Power beaming would be a better option. Short range power beaming is extremely simple. You do not need to reconvert the microwaves back into electricity and the distances involved are modest.
By increasing temperatures to 700 degrees celsius, then you can make iron from the lunar soil.
It does not have to be SpaceX hardware for the Moon Direct Mission. Lunar development can also be done with Blue Origin New Glenn rockets.
Initial missions need fuel before the lunar mining is setup. The lunar mining could be setup robotically first or initial fuel could be prepositioned in storage.
Lunar Excursion Vehicles can be used as drones to explore anywhere on the moon if they rockets for 6 kilometers per second. The moon base would be drone base to explore the entire surface of the moon.