We take our chow / lab mix with us all the time. In fact, he loves to come along and we love to have him along. He's 108 pounds so not a small pup.
Couple things. We leave him alone at him all the time when we go say shopping but he has his 'special place' to stay when we are gone, in this case the bedroom on his dog bed. We take his bedroom dog bed along in the camper so he has a familiar place that he knows is his.
AC on, we don't have ac in our unit and we leave the windows open (with screens of course.
We have a truck camper so space is at a premium anyway. Our pup sleeps on the floor in front of the dining table...
We use collapsable dog bowls for water and food.
We use a retractable dog leash and tie him out when he's outside with it (attached to the camper). We never leave him outside alone.
When travelling, he rides in the backseat (we have a 4 door truck with a full sized backseat), window slightly open so he can get his snout out but thats it. You should never allow a dog to have his head out, they get gunk in their eyes and ears when riding with their heads out....
When we stop at a rest area we let him relieve himelf and we always carry Walmart plastic shopping bags with us to pick up the poop. real simple, no touch and easily disposable in the trash at any rest area. We do the same when camping but we always camp disbursed (never in a campground, we don't like crowded camping).
He's a great companion and with a little common sense, having a pup along is not any inconvenience, in fact, it's a plus.