I've booked a car from Avis in Cabo which looked suspiciously cheap at $41 for 3 days:
Looking for information online it seems that it's a common bait-and-switch scheme where you're shown a low price online, but then forced to buy extra insurance later:
Just like in the U.S., car rental insurance in Mexico is mainly divided into two types of coverage: collision damage and liability. But Mexico has a mandatory insurance requirement that makes declining coverage a potential minefield. The dirt-cheap Mexican car rental rates don't include insurance, which can triple the cost of the rental.
If you don't have liability coverage, you can opt for a Third-Party Liability plan for $15 per day. This insurance covers claims for injury or damage you cause to another driver, car or other property damaged in an accident. This per-day rate for liability insurance is often the equivalent of the weekly rate for the car.
However that $15/day is quoted for Alamo and I cannot find anything about it on the Avis website. Likewise I'm worried that there might be additional hidden fees for car rentals in Mexico. How much should I really expect to pay on a $14/day rental?