You can procure the service by adding the service item to the line.
Steps
Go to Accounts payable > Purchase orders > All purchase orders.
Note
Purchase orders can also be accessed via the Procurement and Sourcing module
In the list, select the desired record.
In the Item number field, enter or select the desired record
In the Item number field, enter or select a value.
In the Unit price field, enter a value.
Note
In normal situation the unit price is populated with a price agreed with the vendor in the trade agreement.
Click OK.
Close the page.