Start with your monthly overhead, adding up storage, vehicle, insurance, marketing, software and anything else you pay for each month. Set the desired annual take-home salary you are aiming for, since that is the goal everything else is measured against, then enter your average projects per month, your revenue per project, your material cost per project and your hours per project.

Add your estimated tax rate so the take-home figure stays realistic, and the calculator returns your monthly profit, your profit margin, your effective hourly rate, your progress toward your salary goal, the minimum revenue per project you need, and a plain-English verdict on whether your pricing holds up.