OK, so renting a car in Cancun/Playa del Carmen can be a little challenging (but worth it to see all of the Yucatán). The rental companies tempt visitors with impossibly low rates ($7/day!) but you will eventually discover that you have 2 options: 1) give them $2500 USD as a security deposit and drive without insurance (Pro Tip: this is a bad idea) or 2) pay about $50/day for full insurance. And with the way people treat cars in the Yucatán, you really want the insurance.
Oh, and don’t think you can get by with your “credit card covering you” because your friend told you that you could do that. That may work in the US, but it doesn’t fly in Mexico. In Mexico, you have Mexican car insurance, or you go to jail until you pay in cash for any damages you caused. You really have to choose one of the two options.
Now, that’s the bad news, but here’s some good news: we have had a fantastic experience renting many times from Edgar Dzul at ISIS Car Rental (Tel.+52(984)879-3111). [Full disclosure: this is not a paid advertisement; we really like them!] Despite ISIS’s name having been copied by a certain group in the Middle East, they are a wonderful family run company in Playa del Carmen and Cozumel that have been there over 20 years and they treat every customer especial.
Edgar’s cars are all fully insured, with no surprises or hidden fees. He stands behind his cars personally, and if you get into any sort of accident or legal problem, you just call his personal cell, and he will come deal with the police for you. In Mexico, if there is an accident, both drivers can be held in jail until the police decide who is responsible and makes them pay. If you have insurance, you might be able to avoid jail, but this is not always true. Having a Spanish-speaking local who knows the police, there on your behalf, is priceless.