Like mundane equipment, it is assumed that the character has enough money or resources to keep themselves in a manner appropriate for the character and setting. However, to take advantage of their wealth they must acquire cards with the Wealth keyword.
Wealth is not the same as money though they are closely related. Wealth can come from ability cards such as Family Wealth which represents the family's general financial standing (e.g. aristocracy) or the ability to sponge off rich relatives. Cards such as this need to be purchased with CP. Wealth can also be equipment cards, normally with the Treasure keyword, looted from defeated foes or given as reward by grateful employers.
Unless the character has either invested CP in a card or gained it through an adventure, they have no ability to use money to their advantage. Thus a prince and a pauper may have very different lifestyles but without wealth cards, neither can use money as an advantage to bribe a guard. The pauper cannot because she has no coinage and nor can the prince because all his money is tied up in property and not available as ready cash.
Wealth cards often have the Discard keyword. Like money, once it is used, it cannot be used again. Cards that represent the character's line of credit, such as Family Wealth, are reusable. Each have their own advantages. Sometimes a character may need the ready cash of a discardable wealth card whereas at other times it is a solid and long-established financial background that is useful.
Wealth cards behave exactly as other cards. They can be played as part of actions when appropriate and available. Generally they are used to influence other people with bribes or to give the impression of power and prestige. If the wealth is being used in an attempted transaction, such as in an attempt to bribe a guard, then should the action fail any wealth cards with the Discard keyword are not discarded. The transaction was not completed so there is no reason why the wealth would be lost.
Occasionally a character will wish to trade one set of wealth cards for another set. This could mean exchanging a valuable but large bronze statue for a more conveniently-sized gem.
To do so, the character performs a narrative action using whatever bargaining abilities they have. Additionally the character may play any number of discardable wealth cards in the action, allowing the character to exceed the normal limits on the number of cards playable. The action dice are rolled and the score calculated.
The resistance is set by the value of the object the character is trying to buy and whoever they are buying it from. The seller uses whatever bargaining skills they have to raise the price (up to the normal narrative limit). Additionally the object being purchased is counted for twice its value, so a 1d6+1 wealth card would add 2d6+2 to the resistance. After all, the seller has to make a profit.
If the action is successful, the played wealth cards are discarded and the buyer gains the new wealth card. However, if the action is unsuccessful, all cards return to the deck as the transaction was not completed.