I have successfully used ferret cages, but not like that one. First is the ability to fall. Beardies fall and that particular cage has falls way to tall. Second is beardies are lazy, your girl will get into the lower levels and not get back up. So no basking or uvb. Third is temp, you'll never keep that cage at temp.
I used highly modified ferret nation cages. By highly modified I mean I installed birtch panels to seal the sides and I glassed in the doors to seal them. That is the ONLY way to keep heat in. I also sealed the ramp between the top and bottom to make it into two habitats.
For the price of a ferret nation cage, the materials to make it usable and the time required to prepare it, your are much cheaper and faster to buy a Zen Habitat or a Dubias.com habitat. Your Zens can be had for 299.00 at last I checked.
This is pictures of what I did. The reason I did it was because I had had ferrets and still had the cages after all my ferrets passed. I would never have bought the cages just to do this project. In the 2nd and 3rd picture you'll see the camera flash in the glass of the glassed in doors. Unless you have the ability to do wood working and to cut glass to fit this is a tough project. Heck even having the tools it was tough getting the glass to fit right. Hours of nipping for little imperfections in the door frames.
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