Roughly what is the size of the safe in the rooms at the poly? I am debating bringing my SLR camera but don't want to carry it all the time. Would it fit in the safe? With or without its bulky bag? Also, I'm assuming the safe is locked with a key... Is the key on some kind of keychain or should I plan on bringing one in order not to lose it (so I can secure the key in my backpack while out and about). Thanks!!