It’s a good question. OCs can decide how to to use common property. We are about to do a similar thing. We have a small-ish common area in one corner of our car park that we think we’ll use for storage. And then ban the storage of goods in actual car spaces (which makes the car park look like a junk yard at times). There’s enough space to give each of our 12 apartments their own locker or small cage.
We don’t really want to get the Plan of Subdivision changed.
So I think we’ll vote for the solution, properly document it in OC records and clearly label each apartment’s locker/cage both in the OC records and on the locker/cage itself. We’d leave any locks to be supplied by each owner. But the locker/cages would stay common property on common property.
I think the key is the documentation of the decision. If it’s not documented properly, problems like yours can happen in the future.