The crystal city location is at a big (like, massive) apartment building.  The lobby door has always been open when I've gone.  Two masked attendants behind plexi-glass at a desk in the large lobby - they're disinterested.  I walk right past them like I live there.  A few times I've been and the lobby is downright bustling - Young, 20s kids with their parents moving their stuff in, late 20s early 30's coming home for work or headed out for the night, Amazon and UPS all around all of which I find ok... hide in the crowd so to speak.  Other times it's been almost deserted.  

Walk through the lobby, along one hallway and down another.  It's a one or two minute walk after you enter the lobby.  

An older guy (mid to late 60s, non-threatening) answers the door with a smile, signals you to take off shoes and points you to the bedroom.  Hands you a bottle of water on the way out.  Some might find the guy off-putting, he threw me a bit on the first visit because I'm used to a pretty young face answering, but it's more or less like mamasan answering at the KMP.

Parking is tough though - I haven't cracked it yet.  There's a parking lot for the apartment but it meanders around the building, it's tight, and it's always packed.  Give yourself extra time to find a spot and you'll still probably end up with a bit of a walk to the front door.