I used an app called CLZ Comics to keep track of everything. Here is part of the statistics information that the app provides.

I should mention that all of the dollar values shown here (except for the total cover price at the top) are pretty much fiction. The app I use assigns these values based on some internal process. It's very difficult to assign accurate values to comics because what you can charge and what you can expect to get depends on many factors, including the popularity of that specific book or the team/characters in it at the time it's being sold, and how long you're willing to wait to find a buyer. Generally, the authority I use to decide what a comic is worth is mycomicshop.com. Many people will use eBay, but that is often extremely unreliable, because the asking prices there are not necessarily what the buyer will get.