I think that is the only rate, as far as I have heard. The whole island is basically the golf course. The only other facility you could use would be the pool or clubhouse. Bobber, any further info since you were there recently?
I am not really aware of the daily rates, as we were staying there. You would best be contacting them directly to see what they offer. The course is challenging, beautiful and well maintained, and the facilities are very nice. I think I put a link in my trip report (trip report section, November) if you need some visuals.
The daily rate is US$150, assuming you make your own transport arrangements. For US$200 they'll fly you from either the Belize City municipal airstrip or San Pedro. Reduce that by US$100 for non-golfing companions.
I was there a few years ago. It was beautiful - I did not golf - just hung out at the pool with the staff. I think the facilities were closed at the time because we were the only ones there (us and 5 others) we took a boat - and it was a long bumpy ride! I loved it.
We went for a day. I managed to get in 18 holes with a couple of rain delays. Unfortunately it rained too hard in the afternoon to play again. Had it been a good weather day, it would have been spectacular. Still not sorry we went.