I used closet cubes. They come in a 20 pack. You hook them together with these little attachments then reinforce them with plastic ties. I wouldn’t use carpet as floors. My rabbit ate some and had to have surgery. You can buy straw mats on-line or from a pet store and use ties to attach them to the floor. My rabbit has never peed upstairs in his house so you don’t need to worry about raining pee downstairs. I think he knows since he climbed up he’s not on the ground?
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