Costco Wholesale Corporation (COST) , renowned for its membership-based warehouse model, recently released its sales results for September. This data offers fresh insights into the company's performance within a rapidly evolving retail landscape. As investors evaluate the performance, a crucial question arises: Should they buy, hold or sell Costco stock?The September sales figures arrive at a moment when inflation, ongoing geopolitical tensions, and a contentious presidential election are influencing consum ...