When I first started out I used regular metal pans, that I soon found would easily rust.
Then, I went to aluminum pans that would not rust ... the chins quickly taught me I had waisted my money there.
Below is an aluminum pan Cotton chewed also.
I then went to stainless steel pans ... about 3 times the price, but they are cleaned easily, almost never stain, look much better and last for a very long time (longer than the regular metal and the aluminum put together - it's seven years later, they still look like new).
Hint: Never clean stainless steel with bleach, it will ruin it.
Wood shelving is easily cleaned with a little sand paper, gives the chins something else to chew on, and can be replaced easily and for a minimal price.
Hint: It is best to tilt the shelves downward towards the center of the cage, very slightly ... this allows any poop and/or urine to roll off onto the floor of the cage instead of poop being stuck to the chin's fur and/or urine soaked up by the fur, staining it.
Jo Ann
P.S. Once I told someone to tilt the shelves to keep the urine and poop from puddling on or sticking to on the shelf, but they tilted them to the outside of the cage ...
... now I make it a point to tell everyone to
tilt the shelves to the inside of the cage.