STL & STEP Prototype Design

I’m preparing a patent-pending concept for a 15-inch, single-piece unit that has no moving parts. To move forward, I need a clean 3D CAD representation that will serve purely as a display prototype. The... (Budget: $250 - $750 USD, Jobs: 3D CAD, 3D Design, 3D Modelling, 3D Printing, 3D Rendering, Fusion 360, Product Design, Solidworks)