I'd highly recommend staying at Kath's place for a large group/family . There are 4 large bedrooms which Kath is happy to configure to suit .....there were 4 adults in our group so we each had a separate bedroom with a luxurious king bed but you could easily sleep up to 9 ( with someone on a trundle) ...There's heaps of room- it absolutely poured the whole time we were in Hobart but the apartment is big enough not to get cabin fever :) and nice and close easy walking distance to Salamanca, shops and sights.
Probably the only thing to be mindful of is the stairs - there are steps up to the back door ( maybe 8 or 10) and the bedrooms are all upstairs however both my 85 year old father and 2 year old granddaughter managed ok.
We'll definitely stay there again next time were in Hobart .