Take your own snacks like crackers, pâté, cheese, salami, olives in tin and packs, stuffed bell peppers.  Most resorts or hotels do a free breakfast(nothing fancy).  Muri night markets run 4 days a week and a $12 meal you'll struggle to finish!  

Food at the markets is also cheap, $10 for ika mata, $2 kebabs, salad, $10 chop suey, these can be taken back to the room for dinner on the beach.

Roadhouse cafe and bar near Edgewater does cheap fish and chips. bring duty free and take cheap soft drinks to mix with.  Drink at happy hour at resorts $10 for a cocktails, cheap beer around town starts at $3 for happy hour.  

Meals at Tamirind house are around $30 but are yummy, Trader Jacks meals around $15-$30, resorts meals are all about $25ish. Lunch at Crown beach resort: $19 for a tonne of tuna, rice and salad.

Scooters are cheap, and getting a rental car is cheap and easy too, these start from $30 a day..... Avis is $50, car a but better quality.  $5 one way on bus, consessions in $30.