The question really focus on the Demand Function and what determine demand from the variables that I share here. I would say demand of electrical devices / software/ cell phones or any other good that Best Buy is famous of selling. Now the variables that determine demand are all listed here and you can choose the variables that data comes handy on among the following:
•Prices of related goods (substitutes or complement)
•Expected future prices
•Income- talk about inferior good if it applies.
•Expected future income of age groups and Expected future credit
•Number of buyers; (population in major areas).
•Preferences- new good or technology, or just new info.