I like the idea of a hospital site more than the idea of an ambulance van/bus/car.
Can still have both but I think a camp is better because it is MUCH easier to defend than a vehicle traveling around picking people up. For one, you can set up sniper guards around the camp site, while a traveling bus is asking to be sprayed with newbie AK rounds while everyone's inside.
Can still use a vehicle to deliver people in need to the hospital site - I just think the hospital site itself would be cooler/more viable in terms of feasibility/survival.
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