With each successful negotiation test, the GM accumulates success points from different rolls, with an allowed maximum. This maximum is determined by the GM based on the rarity of the negotiated items to avoid excessive discounts (typically set at 50%).
The accumulation of points stops when a failure is obtained or when the player decides to stop along the way. The accumulated points are then used to calculate a percentage discount, to which 1 is added. This percentage reduction applies to the total price of the negotiated items.
Additionally, each success also determines the number of items to which the discount will apply.
Example:
First roll: 3 points above the success threshold.
Second roll: 5 points above the success threshold.
Third roll: 4 points above the success threshold.
Accumulation: 3 + 5 + 4 = 12 points, to which 1 is added, making it 13 points in total.
Final reduction: 13% on 3 items.
In the case of a critical success, the discount is 15% (or 15 points above the success threshold).
The new amounts obtained are systematically rounded in favor of the merchant.