while I'm at it,
bike rental starts at $2 a day. good bikes is about $5. i recommend the the shop thats at the left side of ubin village, 2 shops down from the mini coffeeshop. try to negotiate with them and they will usually yield.
a bottle of 1.5L of mineral water costs $1.20. 100plus chilled 1.5L is $2.50.
Thats all I can remember, hha.