If your play yard is going to function mostly as a play space for your baby, or you're on a tight budget, you can probably go with a basic model and skip the accessories such as mobiles and bassinet insert. A pair of lockable wheels or swivel casters on one end of the yard will make it easier to move from room to room. If you'll use it for travel, you'll want a play yard that's lightweight, folds quickly and compactly, and has a carrying case. You may even want to be able to roll the packed unit. A carrying bag that allows the play yard's wheels to roll when it's packed is ideal.
Some basic models may be easier to cart around because they don't have any extra parts. You can also look for bags that leave the play yard's wheels free, so the whole thing can be rolled once it's packed up. If you plan on taking frequent trips (especially by air), you might want to consider a heavy-duty bag that you can buy separately, such as the Rover Gear Easton Travel Yard Bag (about $34).
Perfect for a variety of different uses. Having 3 kids under 5, I've used my fair share of baby gates and play yards. The Evenflo play space is very portable, lightweight and easy to fold down and take on the go. You can add and remove sections with a simple push of a button. I'm currently using this gate to block off my fireplace from my one year old who's fascinated with climbing on it. Also, I will be using it during the holidays to wrap around and block my kids from getting into the Christmas tree. I would recommend this gate.