The current value of the currency.
The item object to calculate.
The tier of the item to buy. Defaults to 1.
The target quantity to reach for the item. If not provided, it will buy the maximum amount of items possible (using target = Infinity).
[amount, cost] - Returns the amount of items you can buy and the cost of the items. If you can't afford any, it returns [Decimal.dZero, Decimal.dZero].
Calculates the cost and how many items you can buy.