Cage Inquiry

I would like to know if it will be ok/safe to have the two story Critter Nation Cage setup for my 10 week old chinchillas? Also I bought fleece and ledges for the cage and want to know will that be ok? I rather not use bedding bc it can become expensive. If I’m using fleece will my chins pee on it? I know I have to clean the cage daily of poop and hay and fresh water but how often should I clean the fleece? Please help