The Vending Machine allows you to sell items to players. They trade in an item, and the Vending Machine gives them something back!
When configuring your Vending Machine, there are two main options to customize: required item and granted item.
If you wanted a player to pay 10 Cash to receive 2 Shield Cans, you would set the options to the following:
In-game, a player can walk up to the Vending Machine and make a purchase (assuming they have enough of the required item). Once the purchase is made, they will receive the item featured in the Vending Machine.
With the Vending Machine, you can also allow players to purchase something that is not an item! A player can buy more health, a speed upgrade, unlocking a gate!