In many ways, Mars is easier. Really the only way it's harder is that it's further away (so it takes more energy and travel time for stuff (both payload and com

In many ways, Mars is easier. Really the only way it's harder is that it's further away (so it takes more energy and travel time for stuff (both payload and communication signals) to get there). The Moon, on the other hand, lacks an atmosphere, has very little gravity, and is extremely resource poor, and has bigger temperature extremes. It presents a lot of challenges that don't exist on Mars (or are substantially reduced). If you want to build a base as a staging area for expeditions, there's no point in putting it on the surface of anything. Just stick it in the Earth-Moon L2 (rather than wasting a couple km/s getting down to the surface of the Moon and back).