I'd say make everything modular. Buy one room at a time and that way the buyer can set it up how ever they want. Give the room a sort of generic set up as far as where the doors, windows and walls are located, then go from there to make one room a medic's ward, another the armory, the next a meeting room, etc, then the buyer can get only ythe rooms they want and arrange them in whatever order they'd like.
Imagine one of Marauder's new interlocking figure stands but with a 10" by 10" footprint. Take two of your rooms, lock them together like you would tow of the figure stands and the door lines up so the figure can go from one room to the next.
Or...keeping the interlocking idea, have the room with four walls, a door in one wall, a window in the opposite wall, lock a couple of rooms next to one another, have a flooring system as a central hallway, then have a couple more rooms interlocked together on the opposite side of the central hallway. The door walls face towards the inside of the building, the window walls face towards the "outside." Think hotel, but offices instead of rooms. A lot of real military buildings are designed this way.
Small props are always a good idea, though I'd check copyright laws for Yo Joe Cola.
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Some people, when trying to avoid thinking about those things that cause them pain, turn to drink, food, or drugs...I turn not to any of those...I collect action figures. Over the years, I've found that alcoholism is much more socially acceptable by far.
