I have the Cavy Cafe purchased from the Guinea Pig Cages Store and in it, I have a 1"X2" fleece liner. On top of the liner, I place a small rug 23" long by 15" inches wide that I purchased from Ikea. I put their hay container on top of the small rug. The rug keeps the liner from getting too soiled and I can easily take it outside and shake the excess hay off of it. I purchased several of these small rugs and I change them out as necessary. I usually only need to change the fleece liner every 3 or 4 days. One of my pigs occasionally likes to go all the way to the end of the Cafe and urinate there.
If you are interested in the Cavy Cafe, I can completely recommend it. My hay is contained nicely it in and my pigs have no problem jumping over the small ledge.