There will always be death and taxes; however, death doesn't get worse every year. - Unknown

The trade system allows players to purchase goods from one NPC trader in one location to resell to another NPC trader in another location for a profit.

Some trade items are only available if you've earned enough influence, using vouchers that can be acquired in the tavern of Necromundus and redeemed in the Portal Plaza.

Because most trade items weigh more than 20 units each, it's important for players who participate in the trade system to own a mount with a wagon installed. (A small wagon will hold 50 units of weight.)

To install a wagon on your mount, you'll need to buy a timber axe, find a timber node, +craft timber, +get timber, then climb aboard your mount and type:

+craft small wagon: Adds a wagon with 50 capacity to your mount. Costs 1440 crafting minutes.

+craft medium wagon: Adds a wagon with 100 capacity to your mount. Costs 5000 crafting minutes.

+craft large wagon: Adds a wagon with 200 capacity to your mount. Costs 10000 crafting minutes.

ONLY craft wagons while on mounts. These items are heavy and cannot be moved once crafted. If you build it when not on a mount, you'll be out all those crafting minutes and still won't have a wagon on your mount.

Information on what you can trade is found in the NecroWiki.