Some balcony doors open outwards---some slide open. For the ones that swing out, some people like to use a bungee cord to hold them open at night. Personally, If I want to prop the door open, I simply put a shoe or some such thing at the bottom of it--- does the same thing as a cord and thats one less thing I have to take.
But, to each his own.
But then the weight of the door messes up my shoe - I tried it once and decided that sliding the bungee cord down in the front pocket of my suitcase is a whole lot easier than messing up a pair of shoes....Doors are so heavy that there are not many items sturdy enough to hold them open.
On Paradise, in the cat. 12 balcony we had there was a hook installed for the door. This was a curse one night, when we opened the door to the passageway, and were just about blown into the opposite wall.
Holiday 5-day Western Caribbean
Liberty 8 day Western