I wouldn't be buying large tranches of Costco stock at this time, but small bites until better prices present themselves will ensure your portfolio can benefit from this fundamentally high-quality business. Worry over the potential impact of a recession is weighing heavily on Costco (NASDAQ: COST), as historically high inflation and rising interest rates could impact the warehouse club's future growth. Costco's stock is down 19% for the year, about in line with the S&P 500.