I haven't stayed at the place myself, but from what I could gather in my search, your hotel is upscale and nice.
Good sized rooms, great pool, and friendly staff. 1 min walk to the beach and 10 min walk to bangla rd.
Couldn't find anything on my initial search on "Phi Phi island lodges."
Bottled beer, water and soft-drinks in a bar is on average 100 THB/bottle. Usually cheaper, but sometimes more more expensive.
1000 ZAR = 6200 THB
http://www.xe.com/ucc/convert.cgi
No need to be nervous. You'll have a great time.