The concern is that you can drive down to the storeroom, not that you can get your car into it - 3x2 lock up is more like bike storage, file storeroom, dry storage for shops/freezer etc.
Value relates to utility. Can you bring your car to it? Is it under a mixed use building ie shops and offices below the residential units?
Otherwise it will be too hard to access and have value only to those within the building.