We have a store room on common property that is used to store some tools and equipment for our grounds maintenance people and a few other bits and pieces. It is locked and unavailable to owners generally to store whatever they like. It does have quite a bit of spare space and I would say an owner might rent half of it (say) from the OC. Just storing your stuff which prevents storing other stuff would be like getting a 'special privilege' which in the ACT requires an unopposed resolution. By paying rent the entire OC continues to get the opportunity for 'use and enjoyment' from this bit of common property. That would be my amateur legals.