Final answer:
The situations where a certificate is needed for a floodplain development permit revolve around requirements for evidence and analysis that ensure the safety and sustainability of the proposed development in the floodplain area.
Step-by-step explanation:
The question pertains to the prerequisites for obtaining a floodplain development permit. A certificate or documentation might be required before such a permit is granted under certain situations, such as evidence of the analysis of flood recurrence intervals or proof of the impact of a proposed development on the floodplain. The examples provided, such as budgeting for product development or the engineering design process, do not directly list these specific situations, but such documentation may implicitly be part of the overall assessment and permitting process.