Recently at one of the RV resorts I saw a 5th wheel toy hauler, the back ramp was down and inside at the rear of the garage area there were four large dog carriers. I spoke with the RV owner, they have show dogs and were attending a dog show near the RV resort. He had two carriers facing the center of the toy hauler on each side. He had placed a box fan blowing air towards the dog carriers. He said they would move the carriers outside under the patio awning during the day when there was shade.
It looked like a nice setup.