Amazon offers Prime members the Hoover 2X FloorMate Tile & Grout 32-oz. Cleaning Solution, model no. AH30435, for $12.68 with free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $6.08.) That's the lowest price we could find by $8. It is 100% biodegradable and non-toxic.