May 2, 2017 Mexico insurance Rules
As you have no doubt read, Mexico has its own unique rules and regulations when it comes to car rental. In a nutshell, some of the cheapest online rental car deals can be found in Mexico, as low as $2 a day in some instances.
What you must factor on top of any online price quoted, from any provider, is the mandatory insurance that must be purchased at the desk.
There are NO OTHER alternate methods of obtaining insurance. No other types of insurance will be recognised. Therefore you must budget between $ 10-20 per day extra, depending on which level of insurance you choose.
Each car type and supplier and location may offer different levels of insurance, simply click on the link TERMS & CONDITIONS next to the photo of the car of your choice, to view the insurance options.
This article helps explain it:Insurance for Mexico
I hope that helps.