Bro, asking hor, this question I want to ask long time ago, those who chiong Batam have they done their maths:
Ferry ticket: S$45
Accomodation: S$30
Booking fee: S$50 to S$80 (average S$65)
Transportation: S$20
Other expenses: S$N
Minimum S$160++, in GL, booking an Indo WL around that price also. But of course, the overall package (massage, food, beer...)much more cheaper