Like many reviewers I too would recommend NOT using Firefly Car Rental out of Sky Harbor in Phoenix. The agent and support staff seemed indifferent to my presence as a customer. The agent pressed me to add auto insurance which I did not need or require. I was also offered the opportunity to return the car with less than a full tank of gas and pay Firefly to fill the tank as if it was driven in running on fumes. In other words I would be charged for a complete fill up at approximately twenty five cents a gallon more than what gas was selling for on the street. Drive the car in needing five gallons to top off and I'd pay Firefly to "fill it up" as if it was empty and, at a higher price. If you've read this far you might predict that the agent was clear that Firefly's charge per gallon was comparable with the street. As for the car two issues arose. The first being that what was available did not include what I'd paid for via my reservation through Expedia. And by this I don't mean that the car was larger. Secondly and the most disappointing was driving off in a car that revealed itself as dirty. The inside of the windshield appeared not to have been cleaned since it rolled off the assembly line. Over a filmy quality the windshield had been the recipient of a spray of toxic-like odor masking liquid which, in the afternoon glare of AZ's sun made for very poor visibility. Finally, the odor masking substance was strong to the point of causing my eyes to feel irritated until the middle of the next day. So, someone might ask why I didn't turn around and drive the car back. Not so easy once exiting the enormous facility and barreling down Phoenix freeway in afternoon traffic. The remedy for avoiding a repeat such as the above will be to never again use Firefly.