Here is a funny story you might enjoy,
We had Chins awhile back. They were soooo cute. We had one who was an escape artist. Found him treading water in the sump pump hole one night after spending hours looking for him. Dried him off and slept with him under my chin all night. He was something else. Finally found out how he was getting out. They were in a nice double high cage and he would climb up and stick his head in every hole til he found the rounded one on the top on the cage that he could sneak through. Needless to say that space was squeezed down immediately. Three escapes was enough!!!
Mumsey's Mouse House