The airbnb is very nice, located really close to Haymarket with several cafes, restaurants, and things to do nearby. If you're there for the festival, it's about a 40-minute walk to most Fringe-related activities, though public transport in the area is good, if you choose to rely on that instead.
I'd primarily recommend this airbnb to couples, as the second bed isn't the most comfortable in the world. But I was able to endure it for 3 nights.
The host was very kind, letting us store our bags nearby before and after our stay, and there were a lot of great looking cafes/restaurants in the neighborhood - I wish I could have checked more of them out!