*My dog (Leo) is trained to use disposible pee pads. I keep the pads in a plastic tray. He uses this area for both poop and pee.
I change the pad after every use. He will NOT go potty on a used pad. If I'm going to be gone for a long period of time, I will put out an extra potty pad (on the floor) in front of the tray.
*We have only stayed in a hotel once, since he has been with us. We just put his potty pad down and show him where it was. I did give him a 'special' treat for using the potty pad in the hotel room. We were in the hotel for 4 days and he only had one accident in the room.
*Once your dog is truely potty trained and can go 'potty' on command. It is easy to lay a pee pad down anywhere and have your dog go potty. I have done this in the back of my suv many times, the airport, my parents house & a hotel.
The only time I have had a problem with my dog being pad trained was during baseball season. My oldest DS plays baseball, which means we spend most of our weekends at the park. I felt really silly laying out a 'potty pad'... on the grass... so our dog could go potty. So, I ended up teach him to go potty on the grass at the park.