catg80 – sorry to be also pessimistic, but if you’re in NSW, the current requirement is that a vendor must annex to their Contract of Sale a print-out of the Title Search, a Sewerage Service Diagram, a Section 149 Certificate from Council, and a copy of the Strata Title Plan; that’s all.
It was your responsibility to commission a Building Inspection and a Strata Search, where in the latter case the Report that you refer to about the extent of the balcony problem and the Minutes of the subsequent Extraordinary General Meeting (EGM) would have been identified and brought to your attention pre. the exchange of Contracts so that you could have made an informed (and possibly different) decision on the purchase.