In this segment from Thursday's Investor Beat, Motley Fool analyst Jason Moser tells investors what he'll be looking for when CarMax (KMX 0.70%) reports earnings tomorrow morning. The company is recommended as a core stock among David Gardner's stock recommendations in the Motley Fool's Stock Advisor service, and Jason will be looking to see whether the company's no-haggle business model is continuing to perform, as reflected by unit sales. Jason will also be watching for the effect the harsh winter weather had this quarter, which hit many retailers very hard, particularly auto dealers.