Looking for a long-term CAD draftsman

We are looking for a long-term CAD draftsman who will help us develop our products. Right now we are looking for someone to improve existing casing/box of our product. It is made from sheet metal (1 mm aluminum), cut and bent to shape, and then assembled with rivets. We would like it to be a lighter and easy to install and assemble.The design you make will be used to make 500 pieces. The main focus of your work in inside the box. Please answer to this question (since we do not read offers that are created by automatic bots, so we ask something that has nothing to do with the business to see if the text is read by a human): is horse bigger than computer. Outside can be as it is. The box contains circuit boards, a power supply and a screen. Please give an example of your pricing and some works you have done.