Quite an adventure ahead of you TLH
I cannot speak on the peculiarities of filming/vlogging/etc. (already well-covered).
Way-Way-Back-In-The-Day, I lived on the Maryland-side (Point of Rocks/Frederick/Tuscarora) of DC for five years; then, I moved to the Virginia side (Fairfax/Vienna/Falls Church) for another ten.
I was young, and straight from the Rural . . . naturally compelled to explore Everything; any chance I could get.
All Of It
I lived (rather PT, mind) with the Homeless and Disenfranchised over an extended period of time; to study, document and understand . . . these experiences were, well . . . *sigh* . . . equal parts "depressing" and "enlightening".
Thesis: "Don't Let Things Come To That".
To-admit, I never lugged-around much in the way of gear (esp. photo/tech (this was before cellular)), but I rarely ever felt threatened; even when on-foot in strange places, at night.
The Metro is fantastic, and is most-ideal for getting in-and-out.
As you might expect in an Urban environ., visitors often face the real need to P&P, but Facilities are extremely limited (usually behind the triage of a Host(-ess) who really expects one to be a paying Customer).
As a young male, I was invariably denied access to any of the rare restrooms in the Metro.
The Museums (Smithsonian, National Gallery, et al.) are Public, and you can usually find (reasonably) timely respite.
I would advise to moderate your caffeine consumption
With regards to "driving", my counsel would be to
not physically drive a vehicle into--and park-in--D.C. . . . use the Lots at one of the terminating stations of any Line, and take the train in.
Metro news and service information for the Washington, DC, Maryland, and Virginia region.
www.wmata.com
You're definitely going to spend $ for parking/travel, but navigating the abject vagaries of navigating "Parking" in the District will cost you time, emotion and $$ (and may very-well lead you to question why you ever got a license in the first place <smile>).
wrt: "9/18, and All That May Ensue":
Remember that the violence of 1/6/21 was with those who found themselves on the Steps (and Within), so gather yourself around the candle of your discernment for proper-placement and situational awareness.
If you know 'People', you know that they always like to talk about themselves . . . a veritable Cornucopia of Stories to be told, and recorded.
Be safe, have fun and do not be afraid (or ashamed) to just Walk Away.
Regards, splifingate