I'm planning to stay at the Georgetown Holiday Inn on Wisconsin and take a flight from DCA. I should be done my meeting by 3:00 pm and leave from the hotel around 3:15/3:30 and head to DCA. How long would it take me to get to DCA by cab on a Friday afternoon around that time? I wondering if I should take the 6 pm flight or wait until 10 pm. I really would prefer the 6 pm, but I don't want to make it too tight either.