We have used Vasa. They are not at the airport but might be able to pick you up. They are very reasonably priced, and their service is terrific! You can pick up in Guadalajara and drop in Manzanillo, but there is a small fee to be able to do that, I think we paid $90 USD. We have had the misfortune of being involved in an accident with one of their rentals, and they handled everything for us in a prompt and efficient manner.
Here is their Manzanillo contact
manzanillo@vasarentacar.comHere is their website [
vasarentacar.com]