Similar corrugated tin texture you've got for the saloon exterior, maybe for the water tower as well? also perhaps with additional combined weathering rust or ochre colored dust layer, relative too the surrounding environment?
Switched the UFO to a Sputnik model (yet to texture), added barrels and trough, worked on saloon interior. Started adding "fun" aspects like graffiti and a disco on the interior lol. I'm going to add a bunch more graffiti but try not to overdo it!