Where can I define the threshold amount?

Go to http://www.apnacomplex.com/main/dashboard
On the left navigation pane, go to Workflow->Approver List Hierarchies
Click on Add New Approver List Hierarchy.
Choose the Approver Lists in the hierarchy.and click “Add” button.
The Approver Lists will get listed. Rearrange the approver lists if required and then enter the threshold amount in the “Threshold Amount” column in ascending order.