Create an Attache Invoice Cost Centre
Navigate to Billing from the main menu
Select Invoice Cost Centres
Click New
Set the Accounting Package to Attache
Select Invoice cost centre rules that are applicable
Click Create
Set Attache Item Codes
Inside the Invoice Cost Centre, click on the Attache Item Codes tab from the top menu.
Click on each Item Classification in the list and enter the corresponding Attache Item Code.
Click Save.
Set Attache Client Codes
Inside the Invoice Cost Centre, click on the Attache Client Codes tab from the top menu.
Click on a Client in the list and enter their Attache Client Code.
Click Save.