User Activity

Is there any way to change my settings so that I get notifications of best offers that are automatically rejected by my value parameters so that I can gauge interest from my main screen without the need to open every listing?
Is there anywhere within eBay to retrieve information on repeat customers or would I need to keep track of this externally? Basically, when someone buys an item from me, is there a tool that reminds me if they have purchased before or is it entirely ...