I have used airbnb quite a bit in the past, and once went into a property (in london) that was so bad that I had to call airbnb. They issued an immediate refund and helped me find an alternative.
I have also stayed in hotels plenty of times, often via booking.com. And if I had a problem, it was sorted out directly by the hotel.
But now booking.com are offering airbnb style properties owned by individuals.
We booked one about a week ago, and were sent the address and details of a key box promptly.
However once inside, it was clear that the cleaner hadn't been. A simple oversight. The bed hadn't been changed, the kitchenette and shower were dirty, and the towels very dirty indeed. It was 7pm, and we briefly considered just making do, but the towels were covered in something ... marital, so we decided we didn't want to have our children (or us!) stay there.
This is where it all started to unravel, because despite appealing to the owner directly, who promised she had approved a refund, and contacting booking.com, and PayPal, we are still in dispute over this. Booking.com is saying they can do nothing because the owner is unreachable. How is that my problem though?! She says she has approved the request. PayPal has not responded at all.
Basically, if you want an airbnb appartment, use airbnb. Your money is not protected in case of dispute if you book via booking.com.