Startup Idea: Multi-Account Management Solution for eBay and Amazon Resellers

Startup idea to develop an application that enables eBay and Amazon resellers to manage multiple accounts simultaneously, with capabilities for receiving sale notifications and storing listing data and photos for future reference.

I am an eBay and Amazon reseller.

I have multiple eBay accounts that I use to sell my items, but I can only sign into 1 account at a time on the iphone app. I mostly use the iphone app to do everything on ebay. I would like to have an app or software on the computer that I would be able to sign into all of my accounts at once and receive notifications that something sold. It doesn't have to do anything other than give me notifications, but if it were fully functional that would be nice too. It would also be nice if this app would allow me to store my ebay listings and photos for future reference, because there is no feature on ebay to do this.