This is a planning framework, not a client case study, a quote or evidence of delivered results. The scenarios describe decisions to validate with the business.
A fixed price can support a clear buying decision when both sides understand the work and its dependencies. It cannot remove uncertainty that has not been investigated.
Fixed scope: make the acceptance boundary explicit
Discovery output
Describe the workflow, users, integration access and assumptions. Use a prototype or a technical check where an unresolved question could alter scope.
Acceptance and exclusions
Define observable behaviour for each deliverable. Name excluded work and client responsibilities so the price is attached to a shared understanding.
Change control
Record new requests, their impact and an approval decision before implementation. Keep defect correction separate from newly requested behaviour.
Can both parties tell whether a deliverable is accepted?
Choose a proposed milestone and write down the review evidence, decision maker and unresolved dependencies. What happens if source data or integration access differs from the assumption? A fixed price is only assessable when those boundaries and the change process are explicit.
How should uncertainty affect the contract boundary?
Consider a separate discovery deliverable when important interfaces or requirements remain unknown. Specify exclusions, client decisions, acceptance handling and how changes are proposed. Support coverage and warranty treatment need their own terms rather than an implied unlimited obligation.
The next step
The Tanvora approach explains discovery, review and launch responsibilities. Discuss engagement scope with the decisions already settled and the uncertainties that need investigation before a fixed-price proposal.