I am planning a 2 day trip to DC. I was thinking of purchasing a SmarTrip card, but since it costs $5 and I will probably be riding the Metro only 4 times while there, I realized that it would not be worth it and I would be better off paying the $1 surcharge per trip. Then, I saw that Baltimore offers a CharmCard which the website says can be used on the DC Metro as well. This card costs only $2.50 and I can purchase it online. But I am unclear on whether the CharmCard also charges a fare without the $1 surcharge, like the SmarTrip card does. Does anyone know?