I tried to use a baby playpen and the problem is that if they have an accident, it soaks into the removable floor. I purchased a Home 'N Go Pet Pen and love it. It has a plastic mat that velcros to the bottom and a cloth cover that goes over the mat and is washable. It also has a zipper front door that folds up and velcros so they can go in and out, if you want. I find my girl goes in there to be alone with her toys during the day.
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