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1. Days and Reference Type = difference between invoice date and due date = here the due date is based on 30 days from invoice date.  Changing the terms will change due dates on all open invoices
2. Order Discounts = automatically applied discount to all lines on an order
3. Settlement discount = A discount that can be manually applied if an invoice is paid within terms
4. Trading Terms (Off Invoice) = A discount that is automatically applied when an invoice is created by creating a credit note for the amount of the trading terms at the time the invoice is created
   1. The credit note that is created will be allocated to the invoice - unless you have selected "do not allocate trading terms credit notes" on the customers "Standard Profile"

Deliver Address

Setup the addresses and determine if they are an office or a delivery address

Image Added

Detailed information is the concertina

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