The other downside is they charge a lot of money for parking everywhere now. So, it might give you some freedom but you will also have to pay for parking and gas.

For example, if you want to go on the Chicken Itza bus tour, don't buy it at your hotel. Go to a local travel agency and get it for half the price. Along the highway that goes from Cancun to Tulum, you can take the Van that both locals and tourists take. I was just there in March and I think they charge like 15 pesos each way.

Cancun isn't the hardest place in the world to drive but with a little knowledge you can save yourself a bundle and not worry about having to get around.