Quite often chins if not regularly bathed their fur can look a bit worse for wear and you will get tufts of hair sticking out.Bath for 10 to 15 minutes a day and hopefully they will start to look better.
A wire cage is what is needed for chins although make sure they have plenty of shelves and maybe a tile on the floor so there are plenty of places for them to get off the wire.
Under no circumstances should you put a chin in the garden and please be very careful at this time of year as heat can kill chins very quickly.

It sounds like they have been severly neglected and could do with some tlc.
Chins do not smell so if their cage is that bad they must have been let get in a terrible state.
Give them a pellet diet and plenty of hay and mini shredded wheats are a nice healthy treat for them.
I would provide them with a nest box and some wooden chew toys and some shelves if you can.Also cuttlefish is very good for them.

I do have some nest boxes for sale on my website if you are interested.Just click on my banner to link to it.

Well done for taking these chins in and don't hesitate to ask advice should you need it.

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