Hi Misty
i also have a apartment in formentera its called picasso facing the orange feilds the green building
we are on the 1st floor and we didnt have security grills but the ground floor did have em
we got broke into they climbed up on the ground floor grills and jumped on our balcony
we did have shutters but they prized them open even with them shutter locks on em
luckily we had just moved in and there was nothing there really to pinch
i went streight back and paid for grills to be put on all over it cost me about 700 uk pounds
now we feel a lot safer
i also know someone who does transfares to and from alicante airport if you want there details pm me