Whatsapp Sender (chrome extension)

Currently this extension is developed for chrome, what it does is send messages to numbers that you do not have registered in your contacts, you can enter what you want and it works excellent, in addition to other functions, I want a developer with extensive experience, which can modify me This extension implementing the sending of images, videos and files and add a delay for that shipment. [login to view URL] I want it to be very clear, the person who offers must give me the real value of the development of the same, time of development, will be discarded that person in the offer say a value and then another. In relation to the payment, 25% will be delivered to start the project, 25% when the developer shows one of the developed options and 50% when the developer allows me to test the extension and know that everything is fine!