There is no universal number. Cover materially different perspectives: sponsor, process owner, frontline users, exceptions and adjacent teams. Add interviews until the picture stops changing materially while ensuring important roles are represented.
Use day rates when buying capacity is genuinely the model. For a repeatable diagnostic, fixed or value-informed fixed pricing usually creates clearer scope and incentives.
What if I am strong technically but weak commercially?
Focus first on positioning, discovery, business language, qualification and proposal discipline. Technical depth only becomes commercially useful when tied to an important client problem.
