Last month when I was in United States I had a layover in San Francisco when I heard a couple briefly mention something about how the city of San Fran was trying to push out companies like Airbnb, VRBO, etc.. I didn't hear why, but it got me thinking and it makes a bit of sense. In a way it's very similar to the Uber vs Taxi Cab fight going on world wide right now.
In case you aren't aware, Taxi Cabs everywhere are waging war against the trendy ride share programs. They are touting claims that these services are not regulated like they should be. They don't have proper systems in place to protect the passengers and even the drivers. There have been stories of Uber drivers with criminal records and lately there was even a rape story coming out of India of a woman being raped by her driver.
Some of this might be propganda, but there's most likely some truth in it. When I think about vacation rentals, or dare I say "home share", the same concerns arise. As a young female solo traveller I tend to be extra cautious when I book apartments. With that being said, there's only so much I can do to protect myself. Until i actually show up and meet my property owner I have no idea who I'm dealing with. At the other end of the table, neither does he.
With this all being said, I don't think it will push me away from sites like Airbnb. When traveling alone, be sure to book only apartments with many reviews. I often try to book places with a female owner as well. Leave the first time visits to a group of buff dudes ;).