Like Silvertwinkie, we travel with 2 large dogs; a Sheperd mix, "Nikita," and a Rough Collie, "Breony." Lately it's been in the 19' Bambi and it's pretty snug with both of us and the pack. Not so bad when the 31' was rolling, but that's in rehab.
We've never been to a park that allowed for unattended dogs outside. And we don't leave them. When we sit out, they love to sit with us and learned the limits of our green carpet "yard" a long time ago. We don't let them leave it or bark (even in surprise) more than once. Children are usually the problem; most have never been taught about other peoples dogs and often run up to strange dogs without hesitation.
When we do leave them in the trailer, we're never gone for more than 2-3 hours without checking on them. The A/C in the 31' never failed us, but the BRAND NEW (and already replaced once) A/C in the 19' tends to freeze if run for hours in extreme southern heat.
They usually like to go with us in the TV anyway and have even learned to patiently wait out my wife's shopping trips. I'm almost that good... sometimes.