I went into the 1 interview with just sending in a meticulous resume with all of my qualifications including a secret clearance and then job offer was graciously offered to me.
I applied through a recruiter. The process took 4 days. I interviewed at Tech Marine Business (Washington, DC) in Apr 2019
Interview
It was one phone interview followed by a 30 minute in person interview. I was supposed to interview with 2 people, but it ended up being one person, my future supervisor.