What you might want to do is have the cage in the room with the door open
most of the time - assuming the cage can 'work' that way.  I'd bet you'd
find times you wanted to confine the ferrets for their own good beyond
just being in their room.  Painting days, certain kinds of visitiors, if
you think about it you can probably come up with times.  If the cage is
their the critters would likely go their on their own if they really
wanted the hammocks.
 
bill and diane killian
zen and the art of ferrets
[Posted in FML issue 1234]