It's tough to tell the taxi companies apart in DC, but if you're heading to Dulles and need a cab, Washington Flyer is a reliable way to go. Their cars are clean, and they specialize in going back and forth from Dulles...considering they have a monopoly on taxi services leaving Dulles. A trip from the District to Dulles will likely run you approximately $50. You can call ahead and arrange a time for one of the cars to come to your home.
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