We met tonight with the landlady and her husband of the apartment we thought we'd be moving to. After we put down a deposit on the apartment, the landlady called and said that her husband didn't want to accept our ferrets. Tonight they came over to see the ferrets and cage. After a brief meeting with them, the husband offered to allow our pets in exchange for a $500 non-refundable pet deposit. (More than double the $200 pet deposit initially agreed to by his wife.)
As such, we've decided at this point not to accept the apartment. It's a decent place, but not a must have, and with them already jerking us around before we've even moved in, this may not be the landlord we want to work with. So, back to apartment hunting we go!