I travel with my cat and he's no trouble. He goes outside, when he judges it is safe. Some places he is outside all day, even naps outside. Others, he does not go out at all or only for a few minutes after dark, when all park dogs are in for the night. He really prefets to pee outside rather than in the cat box.
I was worried, too, before I tried traveling with a cat :). I read everything I could find, here and elsewhere online.
Here are the two tips that were most useful to me:
1. Driveway camp with the cats for a while before you leave, so the rv becomes part of their home territory. I did this for several weeks. A couple of times my cat got annoyed and went back and slept in the house for a night. But I stayed in the rv, and he missed me, so he came back the next might. I knew I had won him over when he stopped letting his neighbor-friend cat in the van because it was his! Now whenever he is spooked he runs TO the van, never away.
2. Your cats will change where you camp, especially if they go outside. They want campsites with good cover, so they feel safe. Shrubs or very high grass. A park that has only mowed grass and limbed up trees, whete everyvrv has a dog, is terrifying to a cat. But a BLM campground full of gophers... that is heaven!
3/4 timing in a DIY van conversion. Backroads, mountains, boondocking, sometimes big cities for a change of pace.
