Integrate Mastercard Open Banking (Finicity) Verification of Assets (VOA) for mortgage underwriting

Steps

1. Register at the Mastercard Developers portal and provision sandbox credentials for the Open Banking US (Finicity) lending product group
2. Create a customer record via POST /aggregation/v2/customers/active (or testing variant in sandbox) and capture the returned customerId
3. Generate a Connect URL for the consumer via the Finicity Connect flow; the consumer links their bank accounts through the hosted UI
4. Once accounts are linked, initiate a VOA report via POST /decisioning/v2/customers/{customerId}/voa; receive a reportId in the response
5. Poll GET /decisioning/v2/customers/{customerId}/reports/{reportId} or listen for the report completion event to retrieve the finished VOA report
6. Parse the report for account balances, 12-month average balance, and cash-flow data; for GSE submission, use the audit copy or the report token for Fannie Mae / Freddie Mac integration