Portability: Are you going to be taking your playpen to other houses? Perhaps you might want to spend a day at the park, where a playpen would be a handy way to keep your baby safe and let them play alone while you read a book? If you think you might be taking your playpen outside of the home, be sure to choose one that can fold up for easy transport.
If you expect to frequently move your play yard from room to room, check its dimensions before you buy. Many interior doorways are only 30 inches wide—no problem for the 28-inch width of most basic models. But many deluxe models are wider—the Graco mentioned above, for example, would be a tight squeeze at 28.8 inches wide. Just be aware that you might find yourself folding a deluxe model to move it around inside the house.
Nice to keep baby out of trouble at home. Once he became mobile we had to do an "upgrade" as we noticed he was starting to hit his head on the X shaped metal bars. We tried some alternatives but the best so far was wrapping the metal bars with pool noodles (see picture). You'll need 8 pool noodles and some cuts (buy some extra in case you mess up). Use 2/3 of a pool noodle to wrap the internal bars and the remaining 1/3 to wrap half of the external bar. The pieces will also need a longitudinal cut along the length to fit the bar in. You'll also need some small cuts in the middle of the longer piece to fit the center rivet, where the mesh is attached to the bars. We got the pool noodles at the dollar store nearby for less than $10 and since ... full review