Shop supports all item economies and all economies running on Vault. If your server uses as economy that does not use Vault, I would highly recommend switching because many other plugins can hook into Vault as well.
The default configuration contains a few variables that you can change to fit your server's needs.
AUTO-UPDATE: change this to false if you do not want Shop to update to the latest version once a new file is released.
usePermissions: change this to true if you want to use permissions. If you do not know what this means leave it as false.
useVault: If you wish to use money instead of items as currency and you have Vault installed, set this to true.
itemCurrency (non-vault): If you wish to use items as currency, this is the id of the item that you will be using. The default item is Emeralds but you can change this to whatever you like.
You can use this full list of materials here to find the material you want to use. Make sure to copy the name exactly (including case).
displayName: This is what your currency will be called. Whether you decided to use items as currency or not, this is the name of your currency that will be displayed. So if you wanted your currency on your server to be called "Dollars", then you would change this to "Dollar" and the plugin will automatically make it Dollar(s).
currencyToStartWith: This is how much money players on your server will start with when they first join the server. Be careful though, if there is another plugin that also gives players money to start out with, you may not want to change this or they will receive more than they should.
maxDurabilityMargin: This controls how "broken" players can sell their items. For example, a player decides to make a shop which sells an item which is at 70% durability. If this is set at 5%, that player will only be able to stock their shop with items that are at 65% durability or higher. Don't worry though, players can check the items stats including durability by clicking the chest of a shop before they purchase anything from it.