120 is quite reasonable i think. :P but of coz you msut know what sort of polish and wax is used on the car. if I m not mistaken, cars is membership based, so you would have to fork out a lump sum as membership and subsequent visits will be cheap.
not that I have anything against them, it would be good to go to a few detailing centers and check out their facilities and work. also if you can, try to talk to their staff or bosses and ask for their analysis of your paint work and also ask what sort of process will be done on the car etc etc. that way not only will you expose yourself to different approaches to the same problem but also what sort of polish and wax they will use.
a few places you can keep an eye out for would be harry bright in kelana jaya, autodetailer in pj, carnuaba autospa in shah alam, plus other car polish centers. :P it is our money that we are spending on the car afterall, so it is best to learn more first and see with our own eyes before comitting to anything.
of coz there is alwyas the DIY alternative. :P Which is the option I am choosing for now. Hehe