HVAC CAD Duct Surface Takeoff

I have a CAD file of our building’s HVAC layout and I need the total duct surface area calculated, but only for a handful of specified units. I will supply the drawing along with a simple list of the units that matter; everything outside that list can be ignored.

Your task is to open the CAD, isolate those units, and produce a clear surface-area takeoff for each one. A concise spreadsheet or table that shows unit tag, duct sizes, total surface area in square metres, plus any assumptions you made will be sufficient. If you prefer, you may also send back a marked-up DWG or PDF showing what you measured.

Please highlight your relevant HVAC or mechanical take-off experience when you reply so I know you are comfortable reading CAD ductwork plans. Accuracy and a quick turnaround are my priorities.