Most standard soil test's are only going to report on nutrient level's. It look's like Guelph University soil testing will give a soil moisture reading, but that isn't accurate because by the time they test your sample, it's dried out. I think you would have to specifically ask for this measurement, and i'm not sure how they would term this, "plant available water" or "soil moisture" or something else, i just don't know. This link might be a starting point.
But you are close to a large body of water and you said yourself that it is very fine sand, so you know it drain's too fast and probably doesn't hold nutrient's well. A good topdresser and a good supply of compost might be the way to go.