Under strata law, every scheme is required to have a 10-year sinking fund assessment which they need to review every five years. Does yours? This is a survey of all the elements of common property, how long they have to go before they will need repair and then how much that will cost.
Oddly, there is no requirement in NSW to fund that projected spending but failure to have any plan to do so would be one of the elements considered if anyone ever mounted an action to replace the owners corp with a strata manager.
The other option is that a strata scheme can apply for loans rather than raising special levies.
The Admin fund can borrow money from the sinking fund but it has to be repaid within six months (I think), although many schemes get round this by recycling the loan every time is falls due.
I would put a proposal to your next general meeting that you initiate a sinking fund assessment and that you decide in advance that strata loans will be sought rather than special levies if any repairs are required and there is no money in the sinking fund.
However, I believe banks are very open to extending your mortgage if you do get hit with a special levy that you can’t pay, as this protects their investment.