Custom bidding website/web application.

I am looking at developing a web application for a new business model. I will try to explain as much as possible using a alternative example; There will be registered users (RU) through an admin panel, which will be in-putted manually by myself/ company staff. Then there will be Temporary Users (TU) whom will come to the site to dispose of their 'goods'. TU will be the customer looking to get the maximum for what they are selling, they will fill out a form, with e-mail address, maybe have an option to add a picture, and important details to value their goods and send it off. This form will be time dependant, and have limited lifespan, maximum 1 day. In this one day the RU will be alerted to this new submission and respond with their offer. The best offer at the end of the time frame (day or 12 hour selection made) will then be e-mailed to the TU with a link to the website to retrieve the details of RU. (The details of each user are not viewable by either users until this point) At this point, details of TU are e-mailed to RU once link is clicked/confirmed. I would like for this to work across mobile phones. This application can be done in wordpress or joomla if possible as a plugin.