That's bad news - I don't know whereabouts on LC your property is situated, but I would have thought one of the permanent residents would have noticed any 'unauthorised' person, whether resident or outsider, climbing over your solarium gate, but I guess it could have been done at night. And it sounds like they were up there for a while unscrewing the bolts - it's a wonder they weren't heard; sound travels so far over there.
I know that most of the residents are very vigilant and do their best to look out for everyone's properties, but on this occasion it looks like the thief has been lucky and got away with it - unfortunately.
What a shame for you and for our little community.