We stayed at Ros's for 3 nights during our trip in Hobart. The place itself is very clean and tidy, and definitely large enough for 2 people, albeit a bit dated. Easy to find and relatively close to the city - almost walkable to the north Hobart strip.
Otherwise a 10 minute to the nearest bus stop with connections to the city / Mona direction. Hobart doesn't have the best public transport, and missing a bus means a half hour wait for the next one. Probably better off with a car.
Also, when it gets windy, the place rattles a bit and can get quite noisy. YMMV.