Our stay at Saladin's apartment was terrific! The apartment is small but well laid-out. We spent 2 weeks there and never felt crowded. Unfortunately, there was road construction being done on the street while we were there, but we know the neighborhood from past trips and it's beautiful. The location is excellent—right off Square Saint-Louis, which is a lovely park, and 2 blocks from Rue Saint-Denis. About 5 blocks the other direction is Blvd Saint-Laurent, also called "the Main" because it's the main drag that separates "east" from "west" in the city. Sherbrooke metro station is close by, so it's really convenient for getting around town.
Olivia was quick to reply to our questions and was really helpful. We were impressed with her excellent communication. We'll definitely consider staying there again the next time we visit Montreal.
*A reminder for Americans: in Canada, "first floor" is what we call the second floor. So there are fairly steep stairs to reach the apartment. But the stairs are straight and concrete, which makes them easier to manage than the typical Montreal spiral staircase.