In general, you want to calculate or guesstimate the expenses required to complete the cleaning, including Fuel, Chemicals, Supplies, and labor (if you are an owner-operator, still consider a laborer cost for your time) +10% for insurance and wear and tear. What I recommend is getting the expertise of a professional in payroll services. I use payrollindex.com. The most crucial factor in calculating is the amount of time any job will take. My cleaning companies generally charge about $150-$200 per hour in residential and $95-$125 per hour in residual commercial work.