What Sharon and the others have suggested. Traveling with over two dogs becomes more work for me but it is a sure way to get more exercise.
Leash training is a must. Also getting them comfortable to elimination on lead. There are sites (and phone apps) that help you locate off lead dog parks.....but I don't count on them. My dogs would rather I walk with them and hike....
In busy parks and with multiple dogs I will use the 6 ft leashes and only go with the Flex lines with one dog...so that I can get the dog in quickly when faced with campground traffic, kids on bicycles, and other dogs. There is usually at least one camper that has a loose dog in each camp ground.
My smallest Remi is a "puppy mill" reject" and came to me with no socialization and a bunch of "fears".....After four years he won't exactly come to me but will stand still and let me come to him. He is wonderful when sitting in laps but others can't try to reach down and pet him while he is on the ground without watching him try to jump out of his skin. When I first started traveling in the rigs I traveled with enough crates for all the dogs. It did take up space but because all the dogs were used to using crates for "feeding" time and some of them for while I was at work....they accepted them as part of their routine. Gradually I have downsized how many crates I need to have. The Golden has one of those cheap soft sided collapsible crates (kept folded up) that I have encase of an emergency and/or a motel stay. The English Cockers have always traveled in their 200 size crate/s. They are so used to crates from dog shows that they will seek out their crates on their own to rest in and in Stuart's case....he is just too interested in everything when loose while when he is crated he sleeps
. The Havenese, Remi (14 pounds), has a smaller crate that he now uses only during dinner times and if I am going to be away from the rig for several hours at a time. I tries a small soft sided crate with him also but he was more apt to flop it over so he has a small solid crate. I pulled my dinette out several years ago because the space left was so much easier to configure with a comfortable chair and changeable # of dog crates as needed and still leave me floor space and walking room....my rig is only 22 ft long. It is all about priorities, training the dogs in basic manners and commands, and determining that sweeping extra hair, wet leaves, sand, gravel and mud out of your rig is worth it. Oh, yes, my rig does NOT have carpet!
When parked in camp grounds you will notice that some campers will tether their dogs to objects or stakes around their site. Other owners use X-pens (they come in 24, 36, 48 in.) When parked for lengthier stays, some owners use either x-pens or orange plastic fencing or light weight wire fencing to stake around the immediate rig area so that their dogs just walk out the door and have their own private area. PM me if you have any specific questions.....