I am planning a trip to New Mexico in the fall, and am certain I will have more questions, but for now I'm wondering about car rentals. My idea is to fly into either Albuquerque or El Paso, rent a car and drive through New Mexico and fly home from the other airport. My question is how much of a premium am I likely to pay to drop the car at a different airport from the pickup and would it be cost effective or should I just plan on returning from the same airport I fly into. I have things I want to see in northern New Mexico and in the Las Cruces area. Thanks for any suggestions.