Hi All - I'm getting ready to tile my 10x7 foot kitchen. I bought the smallest bags of cement & grout at the tile store and paid about $82. I'm sure they're much more than I need. I've seen all-in-one premixed adhesive & grout at Lowes at about $20 a gallon. Someone recommended it because you don't have to worry about it drying out, but with such a small area I don't think that's a concern. However, I'm more comfortable with having it mixed professionally Is this stuff as good as the unmixed stuff? Any clue how much it covers? I've only seen it in white and silver (which I assume means gray). Can it be colored? Thanks!