This attribute can be used to distinguish multiple different Price Specifications for the same Product or Service. It supersedes the former isListPrice property. The following values are recommended:
The absence of this property marks the actual sales price.
SRP: "suggested retail price" - applicable for all sorts of a non-binding retail price recommendations, e.g. such published by the manufacturer or the distributor. This value replaces the former gr:isListPrice property.
INVOICE: The invoice price, mostly used in the car industry - this is the price a dealer pays to the manufacturer, excluding rebates and charges.