I assume that this Chevy Motors office is – given its location (Yaletown) and the era (1920s) – an assembly plant. It may be that there was a sales component, but I have my doubts.Through the set of interior windows to the right of the seated gent, we can see what appear to be racks of equipment — auto parts, presumably. The wooden furniture is exactly what we would expect to see in an office interior of the 1920s.
The man is very likely the manager of the plant. I’m guessing that the exterior windows in his office face west, so it would be early afternoon when Thomson made this image. If I’m right in assuming that the windows face west, the office would be gloomy and chilly in the morning (and I expect that if he had to spend any time in this space in the morning hours, he’d have cause to light the stove in the middle of the room). But on a sunny spring or summer afternoon, it would make a comfortable retreat in which he could get caught up on paperwork.