Many cases end with a small model: units × margin - fixed costs, then "what if price drops 10%?". Consultants build these on paper in the interview and in a spreadsheet on the job.
- Lay out the model in one line: profit = units × (price - variable cost) - fixed costs.
- Sensitivity: change one input and see how much profit moves. Inputs with thin margins move profit most.
- Scenarios: combine inputs into a low, base and high case.
- Breakeven: solve for the input that makes profit zero.
For the spreadsheet side of this work, see the Excel course (absolute references, SUMIF, INDEX and MATCH) and the Finance modeling course.