Miss Hoppy uses Carefresh - that's the recycled newspaper litter you can find at any pet store. That, covered with timothy hay, for munching and rearranging, works wonderfully.
You need a comb-type implement to deal with the undercoat - the brush she gave you is not sufficient for an Angora coat, which is why he's got mats - it's simply not thick/deep enough to reach it all, so it just smooths the surface.
You need a good bunny vet - go to http://rabbit.org - that's how we found Miss Hoppy's excellent vet, but I'm sure there's one closer to you than Wellesley, MA, where she is!
Willow is such a handsome bunny, I am glad he is in a good home now!
As for the wire mesh - we buy mats at Pier One (we like the maize mats) that you can buy in 1-foot squares. Those cover the floor of the cage so Miss Hoppy's feet don't get sore. Other people use carpet remnant squares, even just a sheet of cardboard to give those tender tootsies a resting place!
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