Metal Double Carport Certification Needed

I am a licensed builder, and I install ' Tropical ' roofs over caravans which occasionally include a connected carport. The engineer I have used for years has now retired and so require assistance with certifications into the future... (Budget: $250 - $750 AUD, Jobs: AutoCAD, Building Architecture, Building Certification, Building Design, Building Regulations, Civil Engineering, Compliance, Construction, Construction Engineering, Structural Engineering)