Technical product drawing for prototype

I require an expert to convert sketch drawings for an Apple device case into technical drawings that would be sufficient for me to obtain a prototype of the product from manufacturing industries (either in Europe or abroad in Asia for example). My sketches contain some measures but need refinement. The responder would also need to have an awareness of incorporating technical components within the design. I also require a confidentiality agreement to be in place prior to commencement of the work (see attachment). There would be possible future work after the prototype has been assessed.