Roleplaying Systems

[Polyedit2000]

Here are some additional advices for RPing with currency:

The Travelling Merchant
This kind of shop can move around on foot or with a wagon, meaning that they can set up shop anywhere.  For instance, scalpers can trade you items for money in an occupied city or a merchant might be on the same ship as the party between acts.  The range of wares that can be bought differs between merchants as some may travel with a variety of goods, some sell rare goods, or some might even try to scam.

Pittance for Small Stuff
A pittance is an insignificant cash expense, 1/1000th of your current gold in an example I read.  It's useful for reflecting a person's standard of living without calculating for all the small expenses.  As an example, let's say someone turned in a bounty of 1000 gold and spent a pittance for drinks that costs silver, which doesn't dent their gold, but buying equipment that costs gold will affect their ability to by more drinks.  Ideally, this kind of currency management might be useful in RPs where equipment is very expensive (ie buying mech parts and repairs).

Haggling
This is an interaction between the merchant and the player in an attempt to alter the buying price of a desired item, which goes both ways.  This can range from using a stat to change their mind to offering a service or other items in exchange for said item or lowering its price.  It also goes without saying that haggling too hard can cause the merchant to view players in a negative light. Other RP opportunities with merchants can include stealing and robbing from them.

Paying Off a Debt
In some RPGs like Abyss Cave (RPG Maker) and Evolution (Dreamcast), players have a debt they need to pay off.  In Abyss Cave, gaining that much gold would get you an "ending".  In Evolution, 80% of the boss's bounty is automatically taken to apply to the debt (though you can manually pay part of it too).  Similarly, a "high price" service like the Oddworld Stranger's is also a high-money goal without the restriction of debt.

Riches to Rags
Currency can also play as a person's background, where one DnD example starts the player of a noble background with 10 more gold.  So why not bring more?  One of the more common tropes is that the player might be the heir of the duke who thinks their venture isn't profitable to the family.  Another trope is that the player is kicked out from their mansion by bad guys.  There's also one game where the party helps their cursed cat girl remove the bad guys from the mansion, though the curse alters the DNA enough that the money can't be taken out of the mansion's vault anyway.

Alternate Currencies
Sometimes, the game can prevent you from simply buying your way out by making your currency useless.  This is more common in casinos or festivals where you would need a number of tickets to acquire special rewards or even play some minigames.  Alternatively, some places might have their own currency or do not recognize the global currency; Star Wars Episode 1 made Credits useless, so they haggled their ship into a wager on an upcoming race.

---

Ways To Make Gold:
-Errands/Quests: Simply put, a NPC will pay the player to do something for them.  This can range from being a messenger to dealing with certain enemies.
-Bounties: Some enemies are so dangerous that a prizes is placed on their heads.  A quest merely confirms the reward for dealing with this enemy but is not required to take them down.  At times, a bounty might be place on the NPC you're escorting, making this a tempting moral dilemma.  
-Selling: Because monsters are not likely to drop actual gold.  You can skip this step while keeping realism by "setting aside" those materials and recording the gold you should have by then (which comes into effect when you meet a merchant anyway).
-Salary:  In some settings, you get this just for being on the job, paid after a certain period of time passes.  Alternatively, you can make an arrangement with an NPC to have them pay you for things you can provide on a timely basis (ie donating some rare pet feathers every now and then or becoming a lord and renting out some land).
-Hoard: You might find some gold on the ground from time to time.  This method is actually risky as free gold might either be Mimic bait or where a dragon sleeps.  And in some cases, you cannot gather all of them when a dragon's lair crumbles.

Example Golden Plots
-Mida's Touch: A man is "blessed" to turn all that he touches into gold.  Alternatively, there was an artifact in an Aladdin movie that does the same.
-Golden Egg Goose: A goose that lays golden eggs.  In one story, it was slain out of greed, and in another, it is a giant's pet.
-Alchemist's Stone:  It is a stone said to bypass alchemic restrictions, being able to turn iron into gold or even give eternal life.