Migration south

I'd like to head south this winter in my new class C, spend time in AZ and TX. I don't tow so my current plan is to drive down and spend a few weeks touring, then store it for a month or so and fly back home (Western CO) Spend the winter flying down, touring with the rv for a few weeks and flying back, alternating my winter between home and warmer climes. Is it absolutely imperative to have advance reservations in places like Havasu or Rockport or is it just not possible to wing it a bit and hope for availability around arrival time.