Delivery missions are the best paying missions on the board, they are easy if you know what to do, but they can be a bit complicated if you don't know what you're doing.
Obviously, you need a wagon. But some things are not so obvious.
Here are some tips on how to prepare for them properly and succeed:
1. The missions require you to buy certain trade items from trade managers in various locations. Some of these locations are cities, but some are not, some are nodes. Cities will let you buy items no problem, because you are automatically invested in cities, but nodes will require you to have contribution points to buy the items. So, be prepared and have a few extra contribution points free and ready to invest into a node you need to buy from.
2. The trade items sometimes can fall into level limitation category, like requiring you to be Skilled 5 or Apprentice 10 at Trading to even buy a certain type of goods. So level up trading to Apprentice 10 for a medium mission if you plan to attend one.
3. The trade items in stock are limited supply, but they respawn about every 10-20 minutes at the source node. So give it time, maybe hit multiple locations before returning to the one you just bought up. The mission time is usually 80 minutes, so you can make a couple of trips to find the items respawned.
4. The delivery NPC at the destination may NOT BE the trade manager of the receiving node. This is important, because you can mistakenly sell the goods to the trade manager of your destination. You have to find EXACTLY the right NPC from the quest, it can be a random blacksmith or innkeeper. You do not sell the goods to the node, you turn them in like collectibles.
5. Turning in goods - must be done carefully. Your cart needs to be parked nearby, but you have to be unloading them personally, on your back. You have to be carrying a trade item on your person to turn it in. So unload them manually, while making sure you're not over 100% weight, because the turn-in NPCs are all bugged, they won't deal with you if you're overweight. So be light weight during the unload procedure.