Hi. I am mechanical engineer and ex R&D head from an equipment manufacturer. I have myself written and overseen layout design and descriptive writing of many product brochures, exhibition bromides, product manuals etc., and of course, have used power tools, machine tools etc. extensively.
Having retired from my regular job, I have enough time to devote to your project. My estimate is that each of the longer (3000 - 4000 words) content will cost you INR 10000 and the shorter content of approx. 500 words will cost you INR 1000. However, I have also given an hourly rate, as per the format given.
All relevant technical data will need to be provided by you, naturally, but I can also do some research on related competitor data if required (as a separate task). If this is to be a continuous or repetitive work, we can, after satisfactory completion of the first works, relook at the rates.
Thanks for your attention