I'm not sure if this has been mentioned already...
...but if you have young children and will be staying in a room that has a door leading to a balcony, bring
a small string of bells (like jingle bells) to tie onto the handle of the sliding door.
The doors do have "locks" but they are not child-resistant!
At least if you hear the jingling bells, you know someone is wiggling that handle!!

Of course, children should be supervised at all times, but its so easy for them to get into mischief when you turn your back "for only a minute...."
*Also, to be safe, never leave the chairs outside when not in use. Little ones can push them up to the edge of the balcony and climb up on them so they can see.
Kathy