That apartment is ok if you want a place which is close to pubs and restaurants. The location is really outstanding but also quiet. I personally liked the kitchen which offers everything you need.
The apartment overall is very small and the furniture oldish (it depends surely on your style of living). For what I saw is this place much cheaper than other Airbnbs which reflects in the apartment itself. But again, the location is awesome. If you do not expect a 5* Airbnb you won't get disappointed and you'll get what you pay for. In the non-lockdown situation that place is surely the best located to the Grassmarket, you can get for a fair price.