What is a hot seller
In regards to what ? Water and chickens in Ethiopia ?, Solar water heaters in Siberia ?, Ice machines in Belize ? Cars, Trucks, SUVs, Motorcycles ? Nothing is a "hot" seller because the market buyers will determine what sells quickly and how quickly sells by price and interest. Convertible don't sell in winter but that's the best time to buy one = 4x4s don't sell well in summer but that's the best time to buy one. It all depends on the a-s buying the seat as to how fast it will sell.
Robnick...In reference to the "Hot Seller" indication on a car listing on CarGurus, this simply means that the particular vehicle you're looking at is a popular one, which tends to sell quickly, so negotiating for a lower price will be tougher.