Alex's place is exactly as described in terms of cleanliness, easy access to public transit, and very close to the airport. Beds are comfortable, although the twin bedroom is quite small with no window, so possibly a bit better suited to a child than an adult. The cute, shabby-chic decor, updated kitchen and bathroom, and excellent housekeeping make a flat in an aging building very homey. Alex also provides very good contact and some extras like coffee, tea, cereals, etc. I think it would be a great stay for a family of three on a budget exploring Edinburgh using public transportation.
The biggest challenge for us was parking. We arrived late in the evening after a ferry from the Outer Hebrides and a long drive from Ullapool (catching early flights the next morning), and we really struggled to find a space on the street, even looking in the surrounding several blocks. We talked to a few people on the street in the neighborhood, and they all told us that parking is quite difficult. Alex was immediately responsive when I wrote to ask for suggestions, but I think it is just the nature of the congestion in the city. I would definitely recommend this place if you are able to visit without a car, or trying to arrive a bit earlier in the day to find parking.