Compare the invoice with the signed scope, payment schedule, authorized changes and evidence of completed work. Reconcile described quantities, models, permits and restoration without assuming every difference is improper. Ask for an explanation of unmatched items and keep the response in writing. A payment dispute follows the actual agreement and applicable process, rather than a generic refund rule.
How do you build a reconciliation table?
Start with the approved agreement, not another contractor's price. The question is whether the invoice describes the work and payment stage you authorized. A higher total may reflect an agreed change, while a matching total can still leave a completion item unresolved.
Arizona's ROC recommends reconciling estimates and contracts and keeping payments aligned with the work, with stated exceptions for advance items such as special-order materials and permits. A.R.S. 32-1158 addresses written work descriptions and payment information within its scope. Neither source makes every invoice difference proof of overcharging.
Put the documents beside each other and match the actual items:
| Approved item | Invoice and evidence to compare |
|---|---|
| Original work line | Same location, asset and described task |
| Selected material or equipment | Actual model and approved substitution, if any |
| Change order | Signed revision, adjustment and invoice reference |
| Permit or inspection responsibility | Included scope and current record or status |
| Access and restoration | Which provider completed each agreed item |
| Payment stage | The work or event named in the payment schedule |
| Prior payment | Previously recorded payment and remaining stated balance |
A fixed-price agreement may not be billed like a time-and-materials agreement. Ask for the documentation appropriate to the actual contract rather than demanding a format that was never agreed. Keep taxes, credits or allowances visible where the agreement uses them.
What if a line does not match?
Describe the specific mismatch and request a written explanation. For example, the approved model may differ from the installation record, or an invoice may refer to an unrecognized change number. Ask whether it is a description error, an authorized substitution or a separate proposed item.
Use the change-order record to trace revisions. The equipment substitution review answers whether a different model was accepted. The closeout documents help confirm the installed work.
What should remain in the payment file?
Retain the agreement, approved changes, invoice, evidence supplied and written response to questions. Record the payee and payment reference without publishing bank or customer details. A repair record and an insurance claim are separate decisions; payment documentation does not establish insurance coverage.
Follow the contract's actual notice and dispute process if the issue remains unresolved. Do not infer that withholding every payment, demanding a refund or claiming a penalty is automatically available. Checking quote fairness and questions to ask before hiring concern the earlier selection stage. This check follows the approved job through its billed completion.