Costs behave differently in time, so group them before adding them. Some are consumed in every cycle. Some are spent every cycle but do not rise and fall with substrate. Some run all year whether or not a crop is inside.
Put every bill from one finished cycle into one of the three layers below. A cost you cannot place is usually one you forgot to plan for.
- Consumed each cycle: compost or straw, spawn, casing soil, bags, treatment materials.
- Spent each cycle: labour, power, fuel, water, packing, transport, market commission.
- Running all year: rent, depreciation on rooms and racks, loan interest, your own salary.