For Leslie's second scene in the film (where the camera seems to float down the stairwell) the camera was hung upside down from its support and the image was flipped in post-production.
Every member of the crew has a small cameo (usually as an extra) in the film, with the exception of cinematographer Daniel Grant, assistant camera Maryam Ghorbankarimi and boom operator Nick Sidorkewicz. Nick's elbow was featured in one now-discarded take, but this was almost certainly only an accident.
On a technical scout to Allen Gardens (a downtown Toronto park), Campbell, Grant and Gaffer Danjiel Margetic were approached by a man first offering them drugs, then underage prostitutes, and then employment with him. Security was hired for the shoot in the park the next evening.