Hi bro,
501/532 and 741 are all Chinese massage shop, you can get a HJ at the end of your massage to completely relax your body, the so called happy ending!!
You can ask the ML to take their clothes off for you during the HJ with additonal tips.
These shops are NOT FS places, if you want FS you should always go to a FS place like 5 Star!
However, if the ML has a good rapport with you or you are offering her enough tips, additional extras can be negotiated between you and the girl and there is no guarantee as the same girl can say yes to many people but NO to you or only say YES to you !!
Good luck
Cheers