My husband and I love this product. He tells everyone he knows about what a great job it does. We are restoring a mid century modern home built in 1958 and the Shower Stall and Tile cleaner did an amazing job of cleaning our original exterior concrete walkways and making them look like new. I wish I could find the gallon size in stock at my local OSH Hardware or for sale online. I see that your website sells a 4 pack of the gallon size, but do you have any plans to offer individual gallon sizes for sale online? Thank you!