Where it breaks
Estimating gets sloppy under volume. Sub-contractor management consumes the owner. Re-work creeps. The business gets bigger and the owner gets poorer.
The unlock
Job-level margin reporting, weekly. Operations systems before the next round of growth, not after. Senior estimator. Operations manager. Then the next jump.
When to say no
If a job's projected margin sits below your operating threshold, the answer is no — even if the relationship is good. Discipline beats optimism every cycle.