I have never decorated the OUTSIDE of our door, but did discover early on the fun of collecting refrigerator magnets from all the ports and decorating the inside of the door! They are inexpensive and once we get home we can enjoy them on the fridge at home until we swap them after the next cruise! The grandkids love rearranging the magnet collection on a regular basis! (We also use one of those little magnetic locker cups to keep our key cards and little things in). I am going to try and find some decorations for the outside for our next cruise- it does seem like a fun idea. The DollarTree is a good idea, especially if decorations have a way of wandering at times.