Model the purchasing process
Separate a request for quotation from an approved purchase order. Define line items, units, attachments, quote versions and approval limits. Buyers need a way to compare like-for-like responses; suppliers need a focused view of what they must provide. Preserve changes so an approver knows which version they authorized.
Supplier and staff access
A supplier should see its own requests and submissions, not competing commercial terms. Staff roles may differ for request creation, approval, receipt and finance reconciliation. Enforce those boundaries in the data layer and on file downloads. Invitations and revoked access need tests beyond simply hiding navigation links.
Integrations and exceptions
Identify the accounting or inventory system that owns each final record. Partial deliveries, rejected goods, revised quotations and duplicate callbacks are normal test cases. Use stable identifiers and reconciliation reports so the team can repair missed updates. Avoid assuming a successful API response means every downstream business step is complete.
Project approach
Portfolio examples can help discuss B2B interfaces and approval workflows without inventing cost savings. Bring anonymized purchase documents, current approval rules, supplier roles and integration documentation. Start with one request-to-approval workflow and agree acceptance before broadening the module list. Handover should identify data ownership, backup procedures and responsibility for vendor API changes.