Hello,
I am experienced in development of J2EE AJAX-powered applications (see my profile for details). I can as well get another developers to work on your project.
I can organize development process in stages which includes:
1. Specification (your requirements for the application will be put into written form so that we will be sure that on next stages we get what you want).
2. Architecture (application architecture will be visualized in UML, application will be split into components)
3. Component development - components of application will be developed.
4. Application assembly - components will be assembled together into whole application.
5. Testing of final application.
Actual price for the project would be something around $50k-$100k, it should be negotiated, it would depend on the set of features you would like to have. (So the $300 bid is just a placeholder, not a real one).
Thanks, I am waiting for you response.
Feel free to contact me if you want some proof of my experience or want to discuss some details.