We loved Vincent's flat.
1) The location is simply amazing - the cathedral immediately outside the window (note that it does NOT have bells that chime during the night!), the interesting pedestrianised streets of the old town to wander through, the trams outside the door, and supermarkets just over the square. It really couldn't be bettered.
2) The flat itself is fabulous - it is so spacious - even the pictures can't convey the size, amazing high ceilings and large rooms, comfortable furniture and a comfortable feel (because it really is somewhere that someone lives - not a sterile apartment that is only an airbnb). The two bedrooms are at opposite ends of the flat, giving you privacy. On hot days you can open the balcony door on one side and the windows on the other and get the breeze through.
3) Vincent is very helpful and friendly and very quick to communicate. (Merci!)
We would definitely come back.
NB: As has been mentioned by other reviewers, if you are sensitive to noise, this may not be the best choice. The windows are double glazed and do a very good job of keeping out the noise. However, as it was hot we had the windows open and then, during the day, the traffic noise (including trams) is quite loud. It does become quieter during the night and the double glazing reduces it still more, so we didn't have any trouble sleeping with the windows closed, and it wouldn't put us off coming back.