Washington, DC + Add a trip

Parking is sooo expensive. We are staying at the Doubletree on Rhode Island. I just cannot afford $30 per night. I know that I can park on the street at night but have to move my car by 8:00 am-- that won't do. Let me in on some parking secrets! I am happy to park my car and leave it for the entire stay. We are driving up for a conference so I will not need my car. Thank you!