Is SketchUp very important? For instance can I create what you want in zbrush? Or in 3ds Max and later export it to you as obj or stl file?

Sketchup is the only 3D program I have available. If you can export it to a Sketchup file, That would be fine. I haven't tried importing another 3D file. You can use what program you want, as long as the file I receive is a valid Sketchup file.

I've updated the description of the project for clarity.

I've increased the budget for this project.

could you invite me to this project?...being a chess player very interested.