I'm guessing the closest place to set up might be one of the parks in Arlington. The Crystal Gateway Marriott is pretty flexible, but I suspect even they might draw the line at having a 53x78x29 foot balloon in their main ballroom...
A place to park the rig for the weekend. I know there isn't parking at the hotel.
A place to set up and or launch. If we don't take-off, it is not an aircraft. If we take off, we would have to be very careful about wind directions.
The Marriotts parking lot would probably be too small eh?