When a buyer initiates a trade of multiple items with one seller:
Price negotiations for the entire deal/group, not per individual item.
The total number of items, total price, total carat and trade status displays under Group Details.
After updating the price of the deal, only the total price updates. The $/ct, Rap% and Total $ for the individual item remains static throughout.
Each item's information is listed individually but price remains static throughout, regardless of changes to the group price.