This place is a nice little find. Ideally you need a car (easy shaded parking on the street) but you can also take the ferry to the city with the wharf only a 15 minute walk (then 15 min to Circular Quay).
It is a quite a pleasant waterfront place with a nice deck to chill out on. Very quiet especially at night (except for a bit of noise from the party boats on the weekends out the harbour - hard to escape I guess). The Breville espresso machine was a nice surprise and a decent kitchen to do some cooking, full size fridge, washer/drying etc. Mosman is a nice upscale part of town with shopping and a few good restaurants and coffee places (check out Fourth village Providore for excellent Italian market). My friends and I also had an amazing Japanese meal at Kojiro. Balmoral beach is a short drive away and a nice beach (a bit crowded on weekends).
Would stay here again...