I use a potty training puppy apartment for my Bentley. It has a divider with the small side for a bed and the larger side for the pee pad. When I first got him I would just have him in the apartment. It has a door on both ends and a big one across the front. When he got a little older I added a portable wire play yard to the side of it so he did have extra room to run around.
Here is a so so video of him in it when the cat was teasing him while we ate dinner one night. You can get the idea of what the puppy apartment looks like, but the angle I shot is at the pen looks much smaller than it actually is.