Trading is a feature that allows the player to buy and sell items to another shop for inventory or profit. Most stores use gols as a trading currency, although some stores also use other items, such as Data Discs. Additionally, stores using gols as currency use market price, which determines how much items are sold for on a daily basis.
Each store in Portia sells different items and buys back items in relation to the store type; for example, Alice's Flower Shop buys and sells floral but cannot buy non-floral related items from the player. Stores have a budgeted amount of Gols to buy from the player. Upon reaching that budget, the store no longer buys items from the player until the next day. Additionally, some extremely common items, such as Stone must be sold in higher quantities per 1 Gol, as in a sense of fair trading.
Market price
An 85% market price causing discounts on some items
Market price is a value that determines the sell profit of an item. The base market price value is set at 100%.
There are two prevailing theories as to how the market price changes. the first is that each day themarket prices change in correspondence to the season and weather.[1] The second theory being that if the player buys items from the store, the market price percentage increases over time, and if the player sells items to the store, the market price decreases. It might also be a combination of the two, with buying and selling causing gradual up or down trends in the market and seasons and weather causing small daily fluctuations. More testing is needed.
When market price is below 100%, the selling price of some items decrease: stores sell items at a lesser price, but it also results in buying prices of the player's inventory to decrease as well. When market price is above 100%, the buying and selling price increases. By using market price, the player can take advantage of discounts and price hikes to buy and sell items.
Ratios
Ratios are used to conduct fair trading. Ratios are fair trade defined as a quantitative relation between two amounts showing the number of times one value contains or is contained within the other: in other words, selling x amount of an item provides y amount of an item in return. Ratios are read as "x:y", or "x to y".
As a result, commonly gathered items, such as Wood must be sold in higher quantities per 1 Gol. For example, the ratio of a store buying Wood is "5 Wood : 1 Gol". This means, the player cannot sell less than 5 Wood in exchange for Gols, as this conducts unfair trading. Fair trading is also true for trading one rare item for a large quantity of one item.
Stores
| Store | Type | Owner/Clerk | Location | Daily hours | Operations |
|---|---|---|---|---|---|
 |
Floral | Alice | Main Street | 9:00 - 22:00 | Daily |
 |
Household, Furniture | Gust | A&G Construction, Peach Plaza | 8:00 - 18:00 | Daily |
 |
Exchange | Django | The Round Table | 7:00 - 22:00 | Daily |
 |
Furniture | Paulie | Central Plaza | 7:30 - 18:30 | Daily |
 |
Farming | Nora | Church of the Light | 7:00 - 18:00 | Daily |
| Central Plaza Peach Plaza |
9:30 - 18:00 | Thursday | |||
 |
Clothing | Carol | Central Plaza | 7:30 - 19:00 | Daily |
 |
Consumables | Xu | Dr. Xu's Clinic | 10:00 - 18:00 | Daily |
 |
Consumables, farming | Sophie | Sophie's Ranch | 8:00 - 19:00 | Daily |
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Consumables | Sonia | Main Street | 8:00 - 22:00 | Daily |
 |
Consumables | Martha | Main Street | 8:00 - 20:00 | Daily |
 |
Rare valuables | Mysterious Man | Central Plaza Peach Plaza |
7:00 - | Random |
 |
Equipment | Mars | Central Plaza | 7:30 - 19:00 | Daily |