Hi Steve,
I rented the small family house on this link last Feb
http://www.houseinphuket.com/houses/STR/20041122-p0006/ and paid 30.000 bath for 23 days, there is a shared swimming pool just beside and no one most of the time.
I had also rented a car as Nai Harn is a bit isolated and paid 500 bath/day (cheaper and easier than tuk-tuk if you drive a lot).
The place is great and quiet. 2 bedrooms (but no doors between both
), big living-room with sat tv, big kitchen, nice terrace....
You can see some pics of the house on my personal space on msn :
dlemal@gmail.com