Collective Purcharsing Site (ie Groupon)

I am looking to have a collective purchasing/coupon-deal (example [login to view URL]) site created. I will take care of the graphics, I need everything else done (back-end, front-end non-graphics, user, etc) portions done. I want to make sure that the site is easy to use both front and back-end so people without a lot of computer knowledge can populate deals. I am not looking to reinvent the wheel, I just want to work with someone that can provide customization as we see fit. ## Deliverables Not are requirement, but if a corresponding app can be created for iphone, droid, blackberry, windows 7 phone then we will pay extra per app.