We bought 2 Evenflo Company Inc. 50.-in x 32-in Wood Child Safety
Gatesfrom Lowes for $26ish and then cut up large cardboard boxes to
make them unclimbable. It doesn't allow for much airflow but it works
really well for us in an apartment since it's not permanent and it easy
to take down for guests etc. We attach the cardboard to only one of the
sides of the gate using zip ties or bungee cords. If the cardboard is
attached to both piece of the gate then you cannot adjust the sizing
anymore. The box the gate came in is just about the right size for one
of our doorways so the box is on it's side so the ferrets can go in
and hide but not get through the gate. Seems to work well and is a lot
less expensive than other options I've seen. Good luck on your search.
Luci

[Posted in FML 7812]