General home inspectors are trained to note visible moisture staining. They are not sampling the air, they are not metering wall cavities, and their report language is deliberately non-committal about biological growth.
During escrow that gap matters, because the seller disclosure and the repair request both hinge on evidence. A lab report comparing indoor spore counts against an outdoor baseline is evidence. A photograph of a stain is not.
Timing: standard laboratory turnaround is 48 working hours, so an inspection scheduled early in the contingency period leaves room to negotiate. Same-day and next-day analysis are available when the calendar is tight.
A word on independence: because we do not perform remediation, our findings carry weight with both sides of the transaction. There is no scenario where finding a problem earns us the repair contract.