I use cloroplast and then have carpet squares on top. There’s always going to be pee, especially with a new rabbit and new environment, so I think it’s important to have a water proof layer and then a layer on top for comfort that you can generally clean, but replace if needed.

From experience, tarp like materials like curtains and such make a lot of noise and may be weird to maneuver on, so I would recommend a cheap, water proof tile later/scroll and then see if you can get some carpet squares/cut rugs to nicely fit in, because rabbit feet need something soft and something firm so they don’t develop sore hocks (their feet have no padding.)