I have a couple of 4-foot high ex-pens that I latch together and use on the side of the RV that work very well. I have never had a complaint from the campground if the dogs stay in there, and I always stay with them to make sure. Of course, I stay mostly at state parks and federal campgrounds, and the dog rules at private campgrounds tend to be stricter. One thing to make sure of is that the dog can't get away under the RV. I usually use plastic fencing as an apron on the side of the motorhome, which has usually worked. Some dogs, however, can be escape artists and get right through a setup like that; that's why training is so important, especially with a dog as big and strong as a BMD. Another thing you might look for are private campgrounds that have their own fenced dog park that you can let a dog off leash, as long as they behave. Be sure to clean up after her!