Mate, most insurance companies use an on line version of a "Red Book" or similar to value. This guide will have an upper value or a lower value which are based on many things including K's travelled etc BUT it they do not factor in all those extras that we 4WDers luv to add!
When it comes to AGREED values some companies have some ability to increase outside the guidelines but others do not. Also as there are numerous model variants, perhaps they do know understand exactly which one is yours.
As with anything it is best to shop around BUT just because you get the agreed value you want this year, you may see it drop dramatically next year & have to go through the whole exercise again.
Here is a link, which might help but it may cost you.
https://payment.redbook.com.au/cars/valuation-certificates/personal/car-details?ac=vd&v=Car&mx=cf&tp=pv&refer=GOOG#/{"cbo":{"cboMake":"4294949495","cboModel":"4294843008","cboYearGroup":"4294965738"},"range":{},"multi":{},"text":{"Keyword":"100000"},"tab":"valuation"}