Clear scope.
Clear responsibility.

The written scope defines the engagement.

Before payment, the scope should identify the reporting period, inputs, systems, permitted actions, deliverable format, required checks, customer reviewer, acceptance process, timing, fee, and included corrections.

One cycle is one engagement.

Ongoing operations, software transfer, historical data cleanup, and external distribution are included only if the written scope expressly says so. Changes to work or inputs need an agreed change process.

Acceptance is a review decision.

A required failed check keeps the work in draft. The customer reviewer evaluates the complete package against the agreed acceptance criteria. Passing one check does not establish acceptance or authorize distribution.

Work begins under agreed conditions.

Access, inputs, payment confirmation, and delivery capacity must be established. Delayed inputs or decisions should be addressed under the agreed schedule-change process.