Current thinking is a small/inflatable buried structure with absolute minimal facilities. An inflatable 4 metre diameter tube roughly 6 metre long, laying on its side, buried 2-3 meters, with 2-3 meters of regolith overburden. Say 6-10 bunks on a wall, a couple desks, a RV style shower/head and a small sink. Maybe if we are really lucky a place to heat food. (all inflatable furnature/barriers, filled with varying densities and consistencies of spray foam) There will probably be three airlocks, one outer lock leading to a suit room, a second lock between the suit room and the living quarters as a dust mitigation lock, and a third as an emergency exit. There will be a limited amount of water recycling, and until we get the in-situ resource manufacturing down, most supplies will need to be brought it. Of course power will be supplied by solar panels over the overburden, (A little more protection) and perhaps as a sun shade over some of the external equipment. Power storage for overnight is still in the 'air'. (Sorry) Depending on the location though. (see
Click on thumbnails below for two sized illustrations suitable for computer desktop bitmaps, one is 4x3 aspect ratio, the other is 16x9 wide screen.
An idea to reduce the volume of the payload
By filling the inflatable items on the mission with expanding foam (it comes in various densities) things such as the sleeping cubes, the tables and chairs, and room dividers are all items that can be collapsed to a fraction of the volume of standard items. Since the expanding foam generates CO2 it will self inflate the object.
The foam comes in several different densities - ranging from styrofoam to rock. Filling inflatables with foam will have the benefit of adding rigidity to the item.
This assumes that the foam will expand normally in a vacuum at lunar gravity levels and it should be noted that the foam is temperature sensitive during expansion - extensive testing would be required.
This is another off of the shelf solution available to the mission.