We stayed in Judy's place for 8 nights in November. The garden house is as described and a little oasis in the middle of a city.
Doublebay is a lovely area and well served by public transport and we used the train, 5 minutes for Edgecliffe station, most of the time to get around the city from there. The local area is has plenty of shops and services with a very nice pub , The Royal Oak Hotel , just a five minutes walk down Bay St. We caught the ferry back from Circular Quay a couple of times wand it then a short walk up Bay St to Judy's, just takes a little longer when you call in the pub.
Judy's place itself is a cosy place and we happily spent our 8 nights there. There are some cooking facilities for snacks and things but we were out most of the time exploring Sydney. There is a washing machine and all the other things you need for a trip a away. Sadly while we were there the weather did not give us the best opportunity to use the pool but it was lovely to sit and dangle hot feet in the water after hours of walking.
All in all we would definitely recommend Judy's place for a couple or single traveller who wants access to the city but a quiet refuge to return to in the evening.