I came across this cheap, cool, location. Then wondered how many others are there. Everyone knows about missile silo's for sale but...
Here are 4000+ real Mancave photos that people have created. Some are cool.
My players took over a space port construction facility and started fixing and building ships. I've been in other campaigns where that has occurred.
I had one NPC living in his trashed/crashed Safari ship on the mountain side.
What Player Caves have you and your groups come up with?