High-Precision 3D CAD Prototype Design

I am looking for an experienced CAD designer to create a high-precision, 3D-printable STL file for 6 small character figurine prototype (approx. 70–75 mm height).
The figurine contains an internal cavity for electronics, defined wall thicknesses, and threaded inserts in the base for removable metal probes.
Important:
This project is not about conceptual design or creative interpretation.
A complete technical specification (PDF) with exact dimensions, internal volumes, reference images, and functional requirements will be provided.
The task is to implement these specifications precisely in CAD.
Requirements:
High-precision CAD modeling
Experience with 3D-print-ready STL files (FDM)
Understanding of tolerances, wall thicknesses, internal cavities
Experience with threaded inserts or screw-in metal parts
Deliverables:
Printable STL file
Clean, manifold geometry
Optimized for PLA / PETG FDM printing
Notes:
NDA required before sharing full documentation.
Professional, reliable workflow expected.

The agreed price must include at least one round of minor technical revisions
(e.g. wall thickness adjustments, tolerance corrections, or fit issues discovered during test printing).

„The deliverables include one finalized STL per character (6 total). Source CAD files (STEP) are optional and can be discussed separately.“

Fixed price for the complete scope as described above.

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