The horror stories usually come from people who book the cheapest possible rate on a random site, and then get ambushed at the counter with mandatory insurance that doubles the price, so the smart move is using a platform that shows the full cost, including liability coverage, before you pay anything. Also, stick to recognized pickup spots like the airport or your hotel, rather than some back alley office in downtown Cancun that magically has no cars when you show up. You can lock in a reliable car rental in Mexico with transparent pricing and free cancellation right here https://getrentacar.com/en-US/mexico .