You’ve got a current valuation look at your current pollicy which will show all the valuations you require.
Go online and search for strata insurance and you will be given a list of companies / brokers that supply this. Two big ones are CHU and Zurich.
Some of these allow you to input all the info online and then come back to you with a best quote.
Only info you might be missing is insurance claims for last 5 years (which you need to obtain from SM). I did this recently and left out this info as I just wanted a comparrison with current broker. SM knew I was doing this and his latest quote came in $1,000 lesss than he origionally told us which was less than my best quote so we accepted it.
Remember SM works for YOU and has to do what YOU (strata owners) tell them too and if you want to change your insurance company you can do.