Costco Sale: Wet & Forget Moss & Mildew Remover $19.99

*UPDATE* 7/20/19. Select Costco locations have the Wet & Forget Moss Mold Mildew & Algae Stain Remover (2/0.75 Gallons Concentrate) on sale for $19.99 (after instant savings), now through August 18, 2019. That is $5 off Costco’s regular price of $24.99. Price, participation, and sales dates may vary by location. This product was spotted at the Covington, Washington Costco. It may not be available everywhere. The Wet & Forget Moss Mold Mildew…