Returning stuff to Amazon can get a little tricky in some cases, particularly because of the abundance of third-party sellers ...

Amazon likely has you hooked at free shipping and free returns. Impulse shoppers everywhere love the site because, hey, you have nothing to lose when trying out products from the online retailer.

With that in mind, we've noticed some promising trends at Amazon.com (NASDAQ:AMZN) so let's look a bit deeper. If you haven't worked with ROCE before, it measures the 'return' (pre-tax profit ...