I realized that my Purchase-Based Social Conflict system was missing a key social interaction for D&D: haggling with merchants. Thus, below is a modification of the system to handle buying and selling:

  • Both haggling PC and Merchant choose a social skill (Diplomacy, Bluff, or Intimidate; see skill notes below).
  • Both sides roll the skill against a DC determined by the skill (see notes below).
  • If the roll is successful, the side gets 1 point. For each 5 points past the DC, add another +1 (e.g., rolling a 20 against DC 10 would be 3 points).
  • If the seller got more points, the difference in points is +10% to the cost of the item. If the buyer got more points, the difference is -10% to the cost of the item.

Merchants will generally try to buy from PCs at 50% and sell to PCs at 100% of the listed prices in the book.

The skill used makes a difference:


Roll Diplomacy vs. a DC of target’s Appraise + 10 (or the highest Appraise in the group, such as via multiple PCs).

Rolling Diplomacy assumes the character is being honest about the item for sale’s capabilities (or is acting in good faith when buying). Generally, in a fair trade both sides will use Diplomacy. However, when using Diplomacy, there is generally a limit of 50% modification to any item, no matter the results of the roll:

  • If the merchant is buying, he’s unlikely to argue the PCs below free and unlikely to accept being haggled above more than he expects to sell the item for.
  • If the merchant is selling, he’s unlikely to accept less than his costs and the PCs are unlikely to pay more than half-again the item’s book costs.

This cap may be even less for items that might be slow to turn over: it’s probably easier for the merchant to buy a +1 Longsword at full price but expect to turn it around again immediately than a +3 Merciful Kama.


Roll Bluff vs. a DC of the target’s Sense Motive + 10 (or the highest Sense Motive in the group, such as via multiple PCs).

If a character rolls Bluff, he’s lying about something involving the trade: the seller is inflating the value of the item (possibly ascribe greater characteristics to it) or the buyer is misrepresenting available funds and the market for the item. Using Bluff is not the safest tactic for long term mercantile relationships: just because an item was transferred at a profit under false pretenses doesn’t mean those pretenses will remain undiscovered. So Bluff is generally only a safe tactic when the character isn’t exactly worried about repeat business or getting caught.

Using Bluff does not have a cap for how much the point advantage can be.


Roll Intimidate vs. a DC of the target’s Hit Dice + Wis Modifier + 10 (or the highest total in the group, such as via multiple PCs).

Using Intimidation is usually less about haggling and more about extortion or robbery, or at the very least about trying to scare the opponent about the dangers of not transferring ownership of the item as quickly as possible. In order to use Intimidate, the character must have some kind of power over the target: either a physical imbalance of violence capabilities or the knowledge that the item is very dangerous (to a seller) or potentially lifesaving (to a buyer). In general, characters intimidated into a trade will avoid doing business with the character again if at all possible, so this is really only a long-term strategy for targets such as a criminal fence.

Like Bluff, there is no cap on the point advantage, though the item’s capabilities aren’t misrepresented, just the consequences of holding out for more money.