Why job costing matters
Most contractors know their profit only at the end of a job. Job costing makes profit visible during the job, so an overrun shows up as a $20K problem instead of an $80K one.
The typical gap between estimate and actual on a mid-size project is 8–12% — enough to erase the margin entirely if no one is watching.
The three numbers to watch
Budget vs. committed: what you budgeted versus what you have committed to spend (POs, subcontracts, change orders). If committed exceeds budget in any category, you have a problem right now.
Committed vs. actual: what you have actually paid versus committed. A big gap means invoices are still coming.
Earned value: given the percent of work complete, are you on track? Spending 60% of the budget at 40% complete is very different from 40% at 40%.
Real-time vs. retrospective
Retrospective job costing reconciles at month-end, after problems compound. Real-time job costing updates as work happens — labor from the time clock, materials from POs, sub costs from approved invoices — so you catch drift early.
How CMDBLD does it
CMDBLD tracks committed and actual costs against budget by line, forecasts end-of-job margin from real costs, and a Job Costing agent alerts the PM and owner the moment a line crosses its variance threshold. Payroll and change orders post straight to job cost.