I have 3 of the largest Superpet Deluxe Fun-nel Homes....the one they call
4 floor.  On the stand it stands about 5'8".
 
2 of them are hooked together, and 6 of my girls are in "the Duplex" as
I call it.  I bought ramps, and each cage has about 7 or 8 levels, with
the ramps going between them.  It was necessary, as I have a partially
paralyzed ferret, and she needs the ramps.  I have heard, also, that
forcing a ferret to use the straight tube that comes with the cage as a
means to get from level to level can cause spinal problems...I don't know
if it's a theory based in fact or not, but if you watch a ferret climb it,
it looks a bit difficult.  I just use some chains and hook the straight
tubes up as swings, instead.
 
As long as you keep the litterbox, food dish, and bedding within easy reach
of the 6 doors or the flip-open top, you should have no problem.  The
shelves and the bottom wipe off easily with just a little spritz of water.
 
Hope this helps!
[Posted in FML issue 2940]