Sage Evolution and the Recommended Retail Price(RRP) on stock Item. V7.20 and Up

Hi,

How does the function work? 

I noticed on the Tax Types  there is the option for RRP from which I would assume that either on the Stock Price or Customers’ document it will prompt for the RRP  but it actually seems not to be doing anything. Ideally there should be a slot to put in the price to be Invoiced/billed and another slot for RRP on which Tax will be calculated.