Metro Parking

Refer to the website for general information.

 
Metro operates parking facilities at 42 Metrorail stations. All 42 stations offer daily or hourly parking. Cost: on weekdays, $1 per hour at the metered parking spots (immediately next to the station), or $4.50/day in the covered garages connected to the station; free on weekends at metro-operated facilities; no overnight/long term parking unless you paid for it in advance (see website; have to use pre-assigned level for multi-day parking). When you park on weekends, it is generally considered 24 hour parking; officers monitor cars left over the evening and will leave a notice on your windshield reminding that you have to leave. 
 
In addition to the Farecard (to ride the train) you would need a SmartTrip Card (sort of a reusable prepaid check card accepted only on public transportation system) in order to use/pay and exit the garages at metro station. These cost $5 just to have it, and then you need to add minimum value of $5. You can use SmartTrip card to pay for train or bus ride too (plan to add enough value). 
 
If you come as a group and will drive one car and plan to use metro and park at the metro stations, you could buy one SmartTrip card for driver (to use both for parking and train fare), and the rest of your group can just buy Farecards. 
 
There are few stations at the end of the lines that will accept credit cards (Discover, Mastercard, Visa, American Express) for parking charges: Blue Line - Franconia-Springfield, Largo Town Center; Orange Line - Vienna/Fairfax-GMU, New Carrollton; Red Line - Shady Grove; Green Line – Anacostia; look for signs that tell you which level/exit lane accepts credit cards.
 
Help
Ask locals or station workers.