The Marketplace
The Marketplace Panel (Management Hub, right sidebar) gives a full overview of all trade activity in your society. It has two modes: Sell Orders (Supply) shows items listed for sale by other Cultivators or Seed Industries, and Buy Orders (Demand) shows buy orders placed by Cultivators, plus NPC orders from Seed Industries. Fulfilling NPC buy orders is a reliable way to earn SeedCoin. NPC offers never run out of stock and their buy orders always pay out, so essential goods stay tradeable even when player supply is thin.
Select an item to see its Buy and Sell tabs. From there you can buy directly (transaction completes immediately and the item is delivered to your chosen destination), place a Buy Order, or place a Sell Order (requires a Business Branch). View all your active orders via "My Orders" in the bottom left of the panel.
All transactions use SeedCoin. When you buy, choose which wallet pays, as the wallet's owner becomes the item's owner.
Choose which open delivery business transports the order. To receive deliveries you must have management permission for a building (owner or resident). Select the correct destination inbox: items are hard to find if you lose track of where they were sent.
The market is now truly global, you can browse supply and demand from every society on Avesta in one place. When creating a buy order, pick a shipping package and enable Match Anywhere to find a seller anywhere on the planet. To sell globally, the goods have to reach your society's Spaceport, delivered either by one of your employees or through a delivery business.
If an item isn't available, craft it yourself or ask other Cultivators in Players Chat.
Marketplace vs SEED Store: the Marketplace is in-game trade between Cultivators (and Seed Industries) using SeedCoin. The SEED Store sells items for real-world currency, including Pollen (the premium currency used for Seedling Lives and Pollen Pills). Pollen can also be obtained by trading SeedCoin with other Cultivators on the Pollen Exchange (click your Pollen Wallet in the top-left HUD): place a buy offer at your chosen SeedCoin price for a fixed batch of Pollen (one active offer at a time; reserved SeedCoin returns if cancelled), or accept another Cultivator's offer to turn Pollen into SeedCoin. Offers fill in one go, you can't accept your own, prices are whatever Cultivators agree on, and the exchange spans all of Avesta. Items bought from the SEED Store land in your Cultivator Inventory (via your Cultivator Profile, top-left), from which you can send them to any storage container your Seedling can access.