If you want them to run around freely try the underground fence (of course one that can be set weak enough for smaller pups)!
Or my parents use one that is plugged in inside the house and their pup can go anywhere within 100 ft of the base. I think you can change the distance too. It's just from Petsmart, but even at the lowest setting this one would be too strong for Scooter, so it might not be an option for your pup either.
__________________ Sarah and Scooter   |