Batam getting expensive..many other cheongsters turning to T.Pinang and T. Balai. (T=Tanjong)
Anyway, you can save a lot of money if you can DIY your trip meaning forgo the specific drivers. They will siphon SGD$200-300 plus they will make your cost higher because they will ask for commission at hotels and Karaokes/Spa/ Fishtanks.
On way to save cost is to go to 3star hotels with Karaokes. You will have better bargaining power because you are staying in the same hotel plus you can exchange gals if you find their services unsatisfactory. Yes, mama san will allow you to exchange gals that are unsatisfactory because you are staying withnin the same hotel plus it is safer..the gals won't dare to be funny..eg fake sickness etc.
3star hotels have their own taxis that will take you to where ever you want to go for as cheap asas RP30 000-50 000(about S$6-10) which by the way is the standard price for taxi within the same town..example traveling within Nagoya or Batam Centre. It will be more expensive if you are traveling out of town.
There are many three star hotels in Batam with Karaoke..just do your homework aka surf and search the net. Like wise surf the net for karaokes/spa/fishtanks. Gals pricing are around Rp250000 to Rp300000 (S$36-43)without drivers asking for commission. The drivers commission will jackup the pricing to Rp300 000-380 000.
So be streetwise, if you see a karaoke you want, stop the taxi few shops away..pretend to window shop..basically lose the driver, make sure the driver is gone before you then slowly work yourselves to the karaoke.
This will save Rp250000-400000(S$36-59) for your group.
Ferry Wavemaster for Batu Ampar Jetty and Harbour Front. Penguin and Batamfast for Batam Centre.
Karaoke/Spa /Fishtank are mainly situated in Nagoya..near Batu Ampar Jetty.
Food and Alcohol go to the open makan food courts, they are called "Pujaseru" ..well known ones in Nagoya is Pujaseru A1. Remember to eat food that are straight from the wok and once the dishes and drinks are on the table, make sure two people must sitting on the table..never leave the food and drinks unattended.
Clothings and jeweleries..lose the fancy watches, rings and chains. money break them up. Remember the people there are poor, Rp 500 000 is one month salary for at least 40-50% of the population there. So don't invite trouble.
Ok I think this should be enough info for a budget and safe trip for you and your friends. Enjoy!! =)