A crate is a safe retreat for your dog and should be sized to fit your dog so she has room to stand up and turn around in it. You can downsize a larger crate by blocking off the back. Have a sheet of sturdy plastic cut to fit at a hardware store and sand the edges. As your puppy grows, you can move the plastic farther and farther back in the crate until she doesn’t need the divider anymore.
Gates are an easy way to confine your dog to certain rooms if you don’t want to have a house full of closed doors. Gates allow you to keep an eye on your dog when you’re in another room. They come in different styles, both temporary and permanent. They are readily available at larger department and discount stores and are easy to install.
Playpens can be a great solution if you don’t want to deal with gates. Just be sure the pen is large enough for your puppy to play freely. Many playpens can be used outside, too, and they’re nice to have if you travel. Playpens shouldn’t be used as full-time babysitters, though. Your puppy needs to have some freedom so she can learn what she needs to learn in order to someday have full run of the house.