What the OP first needs to do is to check their Plan of Subdivision.
Victoria is different in this area eg to NSW. In Victoria it’s the PoS, that defines what parts of a strata building are common property and what parts are lot property.
While I agree that the OP’s balcony is very likely to be common property, even substantial parts of apartment buildings in Victoria can in fact be lot property, especially if that part forms no structural element for the rest of the building. For example, I own in a CBD high rise where every second floor structure (and I mean a floor structure within a lot, not a “floating” floor) is deemed lot property as it serves no structural part of the whole high rise building.
As for the poles in the other lot’s courtyard, again Victoria can be different. Implied easements under the Subdivisions Act 1988 allow such things to be in other lots or the common property so again they can can be still a benefiting lot owner’s responsibility to maintain.
So check the PoS first! You must be certain that it’s actually common property.
When it’s confirmed that it is common property, the next issue is how the repairs are funded. Again, Victoria is different in this area eg to NSW. If the OC decides to use a Special Levy to fund the works, as is quite likely in smaller stratas that are not required to have a separate maintenance (sinking) fund, they must then apply the benefit principle when deciding how to pay for the repairs. The benefit principle states that lots that benefit more should pay more. If the works are only likely to benefit eg 2 of the 4 lots, then it’s only those 2 lots that should pay.