Bulk Trader (Fallout Supplement)
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Quantity is the game, and you're the master. When you buy and sell goods, you get a better deal for larger quantities of a single item.
Prerequisite: 6 ranks in Diplomacy
Benefit: +25% more TUs/Caps on selling five or more goods at once, or -25% less TUs/Caps on buying five or more goods at once.
Normal: See Diplomacy and Bartering