I am planning a school trip to Phoenix where we will need to pick up 2 mini vans at the airport. I have hundreds of car rental experience, but I only use Hertz. In looking at prices for this one, Hertz is almost double the price of Dollar or Thrifty. I can't go with Hertz with that big of a difference since we are using money the kids have fundraised. I am looking for a little advice as to which one to go with. I would like to be able to pick up the vehicles and go. Does it really make a difference or is one better than the other?