There are a number of issues here. In the last 3-4 years strata insurance premiums have gone up a lot (more than inflation)
From my experience, where there is commercial activity involved, the insurers see a higher risk and hence higher premiums.
That you are having to go to overseas insurers indicates that the risk , as perceived by the insurers, is quite high (So double whammy)
Unlike the residential strata insurance marker, the commercial strata insurance marker (meaning companies that will carry that insurance is small) the competition is less so the premiums are higher.
Insurers can apply all sorts of conditions before they insure you. Since you done have a lot of insurers to turn to, you just have to comply
(In my commercial block the insurance company wanted us to erect a direction sign outside of a fire exit. Luckily that was cheap but had we not done it we would not have got insurance)
Also I know from my experience that insurance companies are sending out inspectors to commercial buildings and checking general condition and fire services. I’ve never heard of such in a purely residential building.
The legislation allows the OC to on-charge a [lot owner] a higher share of the premiums if the cause the insurance to go up because of the extra risk
But having spoken to an insurance broker (and one that is quite experienced in this type of insurance) I was never able to have explained to me how its determined the extra premium amount.