The flat is on a quiet side street in Marchmont, well-located for access to the neighbourhood's shops, pubs, and restaurants as well as the Meadows, George Square and Lothian Road. It was a great base from which to explore Edinburgh, with several bus routes within a 5-15 minute walk.
Unfortunately we weren't able to meet Brett, but he was incredibly responsive to any questions and left clear instructions for accessing the keys and the flat. He followed up to make sure we got in ok and was contactable throughout our stay.
Parking nearby can be a challenge and if you don't need to have a car, I'd say leave it at home. Nonetheless, Brett gave us some tips and we were able to find longer-term parking not too far away.