Hoover via eBay has select Hoover Carpet Cleaning Solutions on sale from $1.99 each when you purchase 4 or More listed below. Shipping is free.
32oz. Hoover Deep Clean Max Hard Floor Solution 4 for $7.96 ($1.99 each)
128oz. Hoover Expert Clean Carpet Cleaning Detergent 4 for $12.96 ($3.24 each)
32oz. Hoover Stem Plus 4X Hard Floor Solution 4 for $7.96 ($1.99 each)