Convert Cardboard Model to STEP

A cardboard mock-up of mine must become a precise 3D CAD file so the machine shop can start cutting steel. I will share detailed photos, hand-written notes, and the exact length-width-height once we open the project; right now the overall footprint is larger than a smartphone but smaller than a briefcase.

The end goal is a steel prototype that will later receive an anodized finish, so the model has to be design-for-manufacture ready—clear wall thicknesses, proper radii, and no impossible undercuts. A STEP (.stp / .step) file is the required deliverable, with the origin and units set correctly.

Deliverables
• Finished parametric 3D model in STEP format
• (Optional but appreciated) native CAD file and a simple 2-D drawing with key dimensions

Acceptance Criteria
• All dimensions match the figures I supply to ±0.25 mm
• Surfaces are watertight and error-free when imported into Fusion 360 / SolidWorks
• File passes a quick DFM check for steel machining and later anodizing

Please confirm which CAD platform you will use and your typical turnaround time once you see the reference material.