I"ve used all of the above. When my mom died and I had to return to Boise, I left my bike with some warmshowers people - they lived close to the airport and it worked out great.

In Mexico, we wanted to take the train up to Copper Canyon, so we asked around and found a man who lived right across the street from the train station. He let us put the bikes in his bedroom for the week.

And in India we wanted to take the train up to see the Taj Mahal in the full moon, so we left our bikes at a hotel.

Once we even left them in a hotel for TWO MONTHS when we flew from Nepal to Thailand.

People are quite helpful if you just start asking around.