Backend for Submission Form

I have a website that is already made with a submission form. What I need to do with this project: #1 When the submission form is submitted, it should automatically generate an email to the customer with a generic message that I will create. It should also automatically generate a order # in the email. I should also be able to have the details accessible in the backend and choose to edit, or delete the details. #2 I should be able to communicate with the customer from the backend of my website and be able to attach files. There should be a log of histories of the emails that I send to the customer. #3 There will be a testimonial box added to front of page, that consists of an image with the users text that they submitted. I should be able to manage this from backend as well. Because I already have the form made for #1 I do not want to spend more than $50.00 on this website backend. Serious bidders only please. Happy bidding!