Navigate to Admin > Items to view the list of custom items.  The definition of each field is as follows:

SKU: This is the inventory unit that will be used.  It will also be transmitted on any EDI invoice or printed on a printable invoice.
​Description: Will appear on both EDI and regular invoices under the 'part description' line
​Price: The price each for the item.  Please note this value may be overwritten by a user with ah appropriate security level.  To create a coupon, this value should be negative.
​Minimum Price (optional): The minimum price that can be charged for the item.
Maximum Price (optional): The maximum price that can be charged for the item.  
​Default Price (optional): The default price that will be used if min/max pricing is set.
​Default Cost: The amount that will be used for margin and COGS calculations on reports when the custom item is used.
​Cost Category: The category the cost will be recognized in.  Also used to determine appropriate tax type for part, labor, and freight items.
​Type: Currently not used