Dennis,
Bear in mind this process has undergone some change over the last few years & QLD has been different from NSW & other states, but now should be similar.
You really need to talk to the commercial vessel branch of maritime authority, in NSW they're now "Roads and Maritime" maybe qld is harbours & rivers?
In past time post survey of fiberglass vessels was possible but required that reasonably substanecial samples were taken for inspection and testing then these areas of vessel replaced, this is at risk of not passing. Not sure on the age of your design but at times submissions from naval architect could streamline, a submission is required for stability etc. There used to be a simplified process for daycharter only.
The advice I was given by NSW maritime(some time back) over my beach marine cat(there was even a sistership already in survey), was to find a vessel in survey or build)
Without destructive testing or a documented build process with samples created for inspection and testing it could well be the same now. A lamination log showing temp, humidity, resin batches and plys of reinforcement, core materials, quantities etc are usually required, the build premises need to meet a minimum standard, not hard but another hoop.
This may be out of date but the case up till a couple of years back at least, there may be a category that applies, sometimes acceptance of addition of large quantities of buoyancy foam could achieve a daycharter/status.... regardless you will need an NA familiar in the commercial landscape to do the submissions, sometime the sail area is derated also. The resin choice also effects the status, there's plenty Crowther vessels built without csm but utilising other fabrics perfectly strong and servicable but non compliant to Aus standard unless in epoxy.
Most importantly you need to decide whether to compromise your enjoyment of your vessel and sailing to the whims of your paying guests, they soon "suck the life" from a great lifestyle.... Day use is good, 6 hours of exposure & hose the boat down for the next day..
The road to building one will be exxy, you could buy a seawind or another already in survey & keep the crowther for yourself
Jeff