Dear Sir,
I have read your requirements and according to that i will very happy to do the job for you.
Please allow me to work with you. If you allow me once, I will provide the first demo work for your further decision. I know that your time is very important, So I assure you that i will not take much time to make a demo.
I am sure you will find my bid and proposal as per your need, and give me chance to provide first demo work.
Look forward to hear from you