At $25 owner pay per hour, $40 other costs, and 20% margin: 3 hours cost $115 and target $143.75; 5 hours cost $165 and target $206.25. The difference comes from your time assumption.
Write three possible scopes
For each scenario, enter its own owner hours and material cost. Low, expected, and high do not represent statistical confidence bounds.
Recalculate each scenario
Use the full cost and margin formula for each set of inputs. Include helper hours and materials when those change too.
Make a client-facing decision
Quote one scoped price, a staged estimate, or a rate with change-order terms. Explain what would move the job from one scope to another.
When to use this method
Write what makes the low, expected, and high scopes different. Enter each scenario’s actual assumed total owner hours and material cost, then decide which scope you are willing to promise.
A mistake to avoid
Do not call three hand-chosen examples a confidence interval or quote the low case without defining what happens if the job resembles the high case.
What this does not tell you
These are calculation examples using stated assumptions. They are not national service rates, local quotes, tax advice, or a prediction of demand. Confirm your own scope, costs, fee basis, and any local requirements before sending a price.
Source and updates
The formulas and assumptions are explained in our methodology. This guide was prepared on 2026-11-06. If you find an error, send a correction.