Deniss' place was very conveniently located for the Fringe and great for a short stay. We didn't need much communication except for check in where he met us at the flat and went through stuff we might need to know about the flat and the Fringe.
Bed was comfy and room and bathroom was clean - it's a basic flat but it's perfect for what you need, especially if you're not planning on being in the flat very much.
We stayed in the downstairs room, which also conveniently had an aux cable so we could play music and a projector in case we'd like to play a film too. Quiet area and a fantastic view of Arthur's Seat - it's a place I would recommend.