This is a really old picture of the office. My smartphone died during my "before" picture, so I lost it. But the room was painted originally in an ugly cheap flat white paint. It was impossible to clean and I didn't like it.
Like the spare bedroom, I stuck with Sherwin-Williams Showcase in an interior satin finish. It's a high-grade water-based paint. I chose the color Stratford Blue (831) by Benjamin Moore and had it color-matched into the paint I wanted.
This is what it was like when I was done. I painted the trim in the room with a high-gloss white paint as the old paint was either just primer or a flat white. I've had it in this room for a few months now, and the satin walls are so much cleaner and nicer looking that what I was looking at before.