How to require a second approval for large purchases
Above your limit, the person who prepared a bill or purchase order cannot approve it: a second person who approves payments does.
Steps
Set the limit
Choose Purchases → Purchase approvals and enter the approval limit in your currency, including VAT.
Submit for approval
A preparer who tries to approve a bill over the limit gets Submit for approval instead.
Decide
Someone who approves payments (an owner or admin by default) opens it from Purchase approvals and chooses Approve, or Reject with a reason.
Fix and resubmit
A rejected one shows the reason; the preparer reopens it, corrects it and submits it again.