We had one really bad experience, when the owner defaulted on her mortgage and didn't let us know until the week we were all supposed to be arriving. We had booked the house a year in advance for my dad's 75th birthday, and all my siblings were scheduled to arrive when we were notified that the house was in foreclosure and we would get our money back....eventually. And the owner was in England, so it was tough to even get a response from her!
I don't know how we could have avoided this. We rent villas all the time, and this was the only bad experience.