It may be necessary to start your ferret at the top a few times to catch their interest. This gives the ferrets a reason for returning to the tower numerous times, getting lots of healthy exercise. Cardboard mazes are disposable. Ferrets will get bored with the same old maze and will start to ignore its existence. Throw the old one away, get yourself some new, fresh smelling, boxes and start all over.
Boxes are free from any grocery store, and come in a wide variety of shapes and sizes.
Also, should a fight or problem occur, you won't regret ripping it apart to get to the ferrets in trouble. Pipe -If you are looking for something a little more permanent, yet will have enough variety that it will continuously be used. From your local hardware store, purchase slotted sewer pipe . The cost is under five dollars and you don't need a delivery truck to get it home. It easily bends into a compact car.