Get the official record.
Ask for the field notes, soil description, measurements, tested locations, and written agency determination. Understand whether the result applies to one area, one design, or the parcel more broadly.
Ask what process exists.
The agency may allow another area to be evaluated, a seasonal recheck, additional technical work, or review of an alternative system. Availability depends on local rules and site facts; it should never be assumed.
Protect the transaction.
For a land purchase, use qualified real-estate and technical professionals to understand testing contingencies, deadlines, access permission, restoration, ownership of reports, and what result permits cancellation.
Do not treat “an alternative system might exist” as approval or a cost estimate. Obtain an agency-accepted design and itemized quotes.