Our distribution center invoices (utilities/pallets/shipping supplies) - warehouse managers do the initial submit and anything over $5k then goes to the VP of Operations for approval. Sales and Markets get submitted by the initial invoice requestor and then goes to the VP of Sales. It goes to teh VP of IT for approval. All accounting related invoices gets approved by the Controller. All HE related invoices are approved by VP of HR.
As for our organization, the processor entered all the required fields on the invoices then assigned them to the reviewer. The reviewer looks at the invoice and makes sure everything is correct, then submits the invoice to the approver, and the approver is approved. But if the invoice is 10K or more, our CEO will be the last person to approve. Once everything is approved, it will go into the accounting review, and our AP accountant will approve everything on check run and process all payments for the week.