Parking and Directions in Washington DC?

I am going to the DOS office on 301 4th street, Washington dc, 20547, on Friday morning - with a rental car, from the Westin Hotel in Arlington, VA .
If any locals have suggestions for the parking (and cost of) situations near the DC building - will be much appreciated. Need to know if parking in that area is easy/difficult/free/pay (how much)/any parking structure/garage/parking on street, etc.
Also, my appointment in DC is at 10 am - would like to arrive there with enough time to find parking spot, of course - any suggestion on what time should I leave the hotel? Mapquest says that the trip takes about 15 minutes - but, since I am not familiar with the real-time traffic in that area.... any suggestions?
Thanks much!

Agree. Metro is convenient and cheaper. Your hotel is near Metro's Ballston station on the Orange Line, and that State Department building is only a couple blocks from the Federal Center SW station (Blue/Orange lines).

There is limited street parking near there but most of the Colonial Parking garages fill up quickly and early with monthly parking. (Several of the locations are restricted to monthly parking only.) You'd spend an inordinate amount of time trying to find a garage that is not full.

Take the metro. Your hotel is close to the Ballston stop on the orange line. It should take you 20 mins to get there. Traffic will be horrible and parking even worse. If you do drive give yourself at least an hour and a half.

Others have stated the obvious - traffic and parking in DC are terrible. It will not be easy, it will not be free. The Federal Center Southwest metro station is only about a block from the Department of State in Southwest, and that is how I would go.

That said, if driving in IS a necessity, This office is only a few blocks from L'Enfant Plaza which runs a parking garage. You enter from Independence Avenue, and it is for pay. There is little or no free or inexpensive parking in that area. It is likely to cost at least $12 or $15 to park for the morning.

If you drive and park, come early.

To add to the other responses, I'm familiar with your hotel (which is quite new and upscale), and it's an easy five minute walk to the Ballston Metro station. The folks at the front desk can point the way.

Be aware if you decide to drive that traffic patterns from Arlington to Foggy Bottom are complex, particularly during the morning rush hour. There are a number of merges, do-not-turns, and one-way streets. You can also expect heavy traffic, particularly crossing the Roosevelt Bridge into DC.