Master Trader (Fallout)

Master Trader is a perk in Fallout, Fallout 2, Fallout 3 and Fallout Tactics.

Fallout, Fallout 2, Fallout Tactics
You have mastered one aspect of bartering - the ability to buy goods far cheaper than a normal person. With this Perk, you get a 25% discount when purchasing items from a store or another trader.

In Fallout, this perk adds the equivalent of 25 invisible skill points to the player's Barter skill when determining prices.

In Fallout 2, due to a change in the Barter formula, this perk subtracts 25 points from a barter modifier, which is then multiplied by the original price and the Barter skill modifier.

By default, the modifier starts at 100%, but Reaction modifiers can add 25 points, 0 points, or subtract 15 points at the same time, making the discount appear to vary from 20% (when there is a +25 point "negative reaction" modifier), to 25% (with "neutral reaction" modifier (0 points), up to 40% (with a -15 point "positive reaction" modifier).

Fallout 3
With this perk, the price of every item you buy from a vendor is reduced by 25%.