More Space?

When I got my chin 2 months ago, I got him from a breeder. I had gotten another chin from this same breeder before, who suddenly passed very quickly after I got him. Well, when I got both of them, I told her I had purchased a critter nation for him to live in. She told me to only let him live in one part of it (I have a two level) until he is 1 years old (he is about 7 months now). He is tamed and comfortable now, but he seems to be going crazy in the top portion, and I feel he would...

More Space?