Try one of the gay websites to get an idea of some of the venues. Not all places are the same - some have some very hunky guys, some have younger and girlie guys, some have a nice mix. Some gay massage places specify the minimum tip, which usually starts at 500bt, but they expect more. Otherwise, even without the sex you should be tipping at least 500 (and at a gay massage place they won't be happy with that).

If you do just want a massage try the Ambassador Hotel fitness centre, where you can get away with a tip of around 500bt for no sex.

The massage boy getting stuck with a customer who only wants a massage is not a happy chappie.