Rough guess of how many calories are in...?

a local coffee shop I am going to with a friend tonight has frappachinoes(sp?). They seem similar to the ones they sell at starbucks. However instead of light blended they have a no sugar added option. If I got a no sugar added mocha frappachino made with skim milk instead of 2% about how many calories would you guess are in it? I would be getting a small of course.