Confused Southeasterner going west for meeting in Phoenix. Priority sites are Carlsbad Caverns, Sedona, Grand Canyon and perhaps Tombstone just to say we were there, but the turquoise loop sounds interresting. The problem is, I only have four free days. Where should I fly in to start? The smaller airports are pricey. What else is a must see? (I must end the adventure in Phoenix.) Thank you.