At Martin's Tavern, Ryan and Julisa are not sitting in The Proposal Booth. They are sitting in The Richard Nixon Booth, which was Nixon's preferred table during his time as a congressman, senator, and vice president. The plaques were switched to achieve a more symmetrical shot.
While filming on the rooftop across from the White House, the Secret Service would not allow cinematographer Jimmy Ferguson to use a tripod. Ferguson instead used a monopod, and VFX stabilized the footage.
Due to staffing shortages caused by COVID-19, the Washington Metropolitan Area Transit Authority would not allow filming on their metro cars. Instead, filming occurred at the Loudoun County Fire and Rescue Training Academy on a decommissioned metro car, which had previously been set on fire.