One of the importance of having an adequate size cage is that your chinchilla needs a big exercise wheel to be happy. It also needs to fit its dust bath and nest box. in the wild lives in holes and cracks of rocks, it’s why they like hiding in nest boxes. They also have an active life and since you cannot let the chinchilla to roam inside the house, it needs a large exercise wheel to keep it happy and fit. Good chinchilla cages should be able to fit at least these 3 things: nest box, dust bath, and exercise wheel.
This is the most important consideration. Avoid any cage which is painted since the animal might eat the paint. Chinchilla cages also should not have wooden or plastic platforms and levels because your pet can gnaw on the plastic (hurting themselves if they ingest it too) and some woods are toxic to chinchillas if it has high resin content or has been treated with pesticides and chemicals. Choose a safe wood if ever you want a wooden platform. Avoid platforms made from cypress, cedar, chestnut, birch, cherry, mahogany, oak, teak, and walnut because they are toxic for chinchillas. There are over 20 toxic woods for your pet so make sure to research before adding a wooden toy or element in their cage.
i agree that the PVC house is nice and ideal for a sugar glider. but chinchillas have very different needs in houseing from a glider. chinchilla cages need to have shelves and plastic like material isnt good because chinchillas like to chew, making the wooden shelves ideal. for a cage of this size it wont be cost effective, but im currently building one with 6ft X 20in elfa shelving and melamine boards and will be 60in wide X 63in tall X 20in wide. for this size i could not find a cage ready to buy for any cheaper. Using metal and wood only, and making the shelves replacable makes it more suitable for chinchillas than any ferret or bird cage.