The Operating Budget Builder

Build an operating budget for this business/period.

Business: [DESCRIBE]
Period: [MONTH / QUARTER / YEAR]
Revenue assumptions: [VOLUME, PRICE, GROWTH, SEASONALITY]
Known costs: [FIXED COSTS, VARIABLE COST DRIVERS, PLANNED INVESTMENTS]

Produce:
1. A revenue budget built from volume × price, with the logic shown
2. A cost budget split into variable (driven by volume) and fixed
3. The resulting profit, month by month if seasonal
4. The key assumptions listed separately so I can flex them
5. The two or three assumptions the whole budget hinges on

Build it so I can change one input and see the effect — tell me which
inputs those should be.