A good friend of mine lived alone in a 5-bedroom house. He had an ice-climbing room, a rock-climbing room, a backpacking room, a caving room and a skiing room.
Okay, here's my base camp. It's in the basement, everything is on rolling carts for ease of movement and cleaning. There's a lot of cross-over. A lot of climbing hardware is stored with the caving gear. A lot of my climbing clothes are stored with the skiing gear. Behind all of the carts are a bunch of messy shelves stacked with sleeping pads, sleeping bags, etc. The rolling carts really hide the mess. I found that dehumidifier in the basement really keeps everything dry and free of mildew.. I have two more rolling carts in the garage, when I come back from trips I just hang everything to dry in the garage. When the season for that sport is over, everything gets moved to the basement.