Without consulting reviews I used booking.com to book a room in Washington DC. When booking it the site showed $0 to cancel or change the reservation.
The short version is that I inadvertently booked the wrong date. I was charged in spite of emailing immediately, not days later, not hours later, literally within minutes.
I just noticed yesterday on my credit card bill a third charge for another date I didn't book.
As to ease of use. It was easy. As to explaining how to correct a mistake or dispute a third charge, there is nothing.
Hopefully this scam site is run completely out of business sooner than later.
Just to be sure, I am filing a Better Business Bureau compliant since their site is not designed to assist with complaints. They roll it to the hotel which rolls it back to booking as the agent.