Steve H over on DP forum explained RRP and MAP.
RRP is the same as Australia - Recommended Retail Price. That is what Minelab suggest is a reasonable price to charge. For the GPX 6000 in the US that is $7,499.
MAP is Minimum Advertised Price. That is the minimum that dealers can advertise the price. For the GPX 6000 in the US that is $6,000.
So, almost all dealers are likely to advertise at the $6,000 price otherwise they are going to be missing out on sales.
$6,000 US is roughly $7,900 here so $1,500 ish below GPZ price.
Apparently the MAP is the minimum advertised price and once speaking directly with the dealer they can sell the detector for cheaper than that or throw in as many extras as they like - they just can't legally advertise below that price.
But that is all in the US. I'm not sure about how all of this pertains to Aus.
I'll try to link in Steve's explanation - might be better than mine :Y:
EDIT: 3rd page of this thread at the bottom of the page.
https://www.detectorprospector.com/forums/topic/15071-gpz-and-gpx-pricing-compared/#comments