How high does a bunny cage need to be?

If its outdoor, then you don't need a liner. Just caging for the floor. If its inside, then building a frame with plywood under it. And stapleing a shower curtain over the wood bottom to protect it..super tight. And dumping wood shavings like pin would be the best. They need some kind of absorbant floor cover.they pee ALOT! They also eat fabric and everything else they can get their mouths on. Wood will be chewed. Fencing climbed and tested. It may be easier and cheaper to go on WWW.Craigslist.org and type in your area. And type in rabbit cage in the search box. Sometimes they are even free. People just wanting something out of their garage.