Random business idea: AirBnB but with verified properties. Actually AirBnB can do that themselves easily enough, just hire people to check properties. Or hire secret guests, if the renter redirects the user to another property, withold payments / ban them from the site.

But quality is not in AirBnB's interest, apparently - being cheaper is. They get a cut from all financial transactions anyway. Once they're listed on the stock market the people currently running it can retire and it's no longer their problem.