Stayed at Arnaud's for four nights with my family (wife and toddler). Experience was good overall, except for what seemed like a few miscommunications between the host and contractors. Once, we arrived back at the apartment to find that the cleaners had entered, mistakenly believing that they were supposed to be cleaning in between guests that day. On a different day, we came back to the place to find people in the middle of painting the front steps, making it difficult to go up to and down from the apartment. And the day we left, the cleaners had arrived and entered before our check-out time. As others have noted, the apartment is on the third floor, and stairs (front and back) quite steep and narrow. Could be a challenge if you have mobility issues.
The apartment was typically true to the pictures. Main difference would likely be that since it is summer, the window in the bedroom has an air conditioner, which was great and helped with white noise to cover sounds from the street at night. However, the AC unit left half the window open except for a piece of foam, which could easily be pushed out and therefore cause a fall hazard for a small child. While there is a balcony at the back, there were various objects that could have been cleaned up (old air conditioning unit, large 2x4, etc.) to make the space nicer.
Otherwise, place was very clean, kitchen had everything for cooking, great to have access to a washer and dryer, and it was conveniently located (short walk to metro, cafes/restaurants on Ontario Street, and parks for children). Parking space also an added bonus. Arnaud was also very responsive to my questions, and accommodating when I asked for an earlier check-in time.