Cost tracking
Watching spend against estimate while there is still time to act on it, rather than reading the bad news at completion.
How to track actual costs against a fixed price statement of work
A fixed price SOW gives you one number and no invoice line to check yourself against. Convert it into a cost ledger, then reconcile actuals every week.
How to tell if a fixed-price job is losing money before it finishes
A fixed-price job goes wrong in week three, not at the final account. These are the leading indicators that show it, and the weekly checks that surface them.