In Freshly-Picked Tingle's Rosy Rupeeland, wallet and life are one. Tingle's health meter is his Rupee meter. If he has no Rupees left, he dies. The whole game revolves around losing and gaining money, making survival a delicate business.
The Rupee System
Freshly-Picked Tingle's Rosy Rupeeland has a payment system implemented to ensure people won't get stuff for the absolute lowest price by offering a low amount of money and then adding a small amount of Rupees to each new offer until the character or object accepts the offer. In most of the cases, if an offer is made that is too low, the character or object will just take the money offered without giving anything in return. The given money does not count towards a total and is simply lost. Similarly, there are situations in which you can ask what amount of Rupees you'd like to have. If you are able to choose what amount of money you want for an item (most items have a fixed price) and you can ask too much, you get only 1 Rupee and the item is simply taken from you. If you are offered a reward for a good deed and you ask too much (the number of chances you have to ask for a proper price depends), you won't get anything at all.
Only a few exceptions exist. The guys repairing the bridges, dungeons, the tower and a few others add what is given to a total.
Trading
In the whole game, you'll encounter only one person who won't ask for money for a certain service. In fact, most of the people of the town nearby Tingle's house won't even talk to him if he doesn't pay them first. And that is only the beginning. Those willing to talk to you usually want money for what they have to say (information). Depending on how much they are paid they will tell only a certain amount of what they know. The full message can still be obtained by paying the full amount of money. Tingle also has to pay for tools and other services. An interesting note is the game hardly ever requires you to buy/pay for something. It's entirely up to you whether you try to figure out things on your own or need a little help.
Tingle also has the option to sell items he acquires on his quest. Except for a few special "sidequest" items, none of these are worth much, but the supply is unlimited. For better money, Tingle can also attempt to cook new items out of the old ones (listed as "ingredients"). These new items (among which are healing potions) have to be carried in bottles, but are worth significantly more and selling them to the right person can unlock new stuff.