
If that basic math is processed every time then I have no problem, but what it appears everyone is saying is that its acceptable for it to be [b]Cost * Variable Margin Dependent on Cat Type = Customer Price[/b]
Bizarre

This is because PD secure a very competitive discounted price on the CAT 1's and 2's bricks due to the volume purchased across the entire group. Then, when they add their "profit margin" on top the price is probably similar or slightly more than retail.
With the less popular bricks, volumes as less so less discount is available to PD. Once PD then add their "profit margin" on top of this, the price is a lot higher. Hence the discrepancy.....
I would suggest that the profit margin % that PD place on any item remains relatively constant.
This explains why, for example, customers only have a very limited choice when it comes to Basins and Tapware. I personally found this frustrating especially as in some cases the style of tapware did not suit the style of basin !!! But of course, if every customer can only select from 4 basins, PD will not be paying very much per item for those items due to the high quantities involved.....