I got a nice welded wire pen at Tractor Supply- 10 X 10. I put down sand and then pavers from the home depot. We have a deluxe dog house and I also bought the sun cover for the pen. Its nice and cozy and easy to clean. I like it for when I am going to be gone for a couple hours instead of leaving him in his crate since he is just a pup and can't hold it for long. I am thinking about taking out a few pavers in the area he usually "goes" and putting a piece of sod there- but knowing Radar he would have a field day tearing it up and then eating it! Anyone else try sod in a pen with a pup?