It's getting easier and easier to travel with dogs if you're driving. Hotels are becoming very accommodating and there are books you can buy that have dog attractions across the country.
Hugs to you for considering taking on a dog that needs a home. Do the try-out! See how happy you are with one of them and see how well your son does. If he loses interest and you aren't happy with the idea of caring for another being, then don't fret about not taking it on, but you might surprise yourself and get gushy over the munchkin.
Human salvation lies in the hands of the creatively maladjusted.
Martin Luther King, Jr.