This subsystem uses figures, scores and terms form this post on Reputation and Grace.
A man lives by his word and deeds not simply by the weight of his coin. Trading and the related Haggling is most certainly influenced by Reputation. Presented here is a simple system for trading based on Reputation that gives a little room for wheeling and dealing without dominating too much table time.
Trading is handled by a roll on Reputation Table IV: Trading/Haggling. To conduct a bout of Trading over the price of a good the customer offers a Bargain Price against the Asking Price of the seller. Differences in the price are compared, modifiers applied to a roll of 2d6 and the table consulted.
Merchant Trading Score is required for a merchant. This is simply a score of 0 to 5 that describes how hard a merchant haggles a 0 is inexperience or poor skill while a 5 is a very skilled and wily tradesman.
Modifiers to Roll:
Apply Customer Reputation Reaction Modifier.
Apply Customer CHA Reaction Modifier.
Subtract Merchant Trading Score.
If Bargain Price is approximately 75% of asking price subtract 1 from the roll
If Bargain Price is approximately 50% of asking price subtract 2 from the roll
If Bargain Price is approximately 30% of asking price subtract 4 from the roll
If Bargain Price is approximately 10% of asking price subtract 8 from the roll
If a player is trying to sell goods one may apply their reputation based reaction modifier as the Merchant Trading Score. If the merchants other scores are unknown simply double the Merchants Trading Score and then add to roll.
A player is never compelled to buy an item but refusing the deal can result in a loss of Reputation Points now and again. The "Snookered" result compels purchase at the cost of Rep Pts for refusal.
If one refuses a Bargain Priced result a Grace Save may be required by the DM or the customer faces a loss of 1d3 Rep pts.
Refusing a gift may or may not have further complications at the DMs whim and the situation at hand.
Failure to buy more (at 50% or more of asking price) in a year (or next time identical goods are purchased if sooner) costs the customer 1d6 Rep Pts. No save allowed.
Accepting 3 or more gifts without offering a noteworthy gift in return costs 2d6 reputation, a Grace Save will halve this loss.
There is a 1-3 chance (in d6) an Insulted Merchant may call upon guards or other help to eject a customer. Active roleplay and a Grace Save will mitigate this result.
There is a 1-4 chance (in d6) an Outraged Merchant may call upon guards or other help to eject a customer and even react with violence. Active roleplay and a Grace Save at -4 will mitigate this result.
Merchants are usually clever or cautious enough to avoid harm so a DM is cautioned to gauge Merchant reaction carefully.
If a confrontation with a merchant results in harm to the merchant, his property or guards the offender may face legal issues and a loss of reputation of 6d6 if a Grace save (half on save) is failed following the incident.
Trading/Haggling is presented as an option and clearly wouldn't fit every campaign or every shopping trip in play. It's up to the DM to determine when this subsystem will see use.