Hey, this is semi-legit. You won't offend them by asking if there's extras been provided. Usually I start with casual talk....Anything...Weather, food, different countries, cultures, etc...then, throw in like you hurt your neck for staring to beautiful girls...and it's why you end up on their spa to get it fixed
...Blurt out any you can think of, surprise yourself and enjoy. Be nice, gentle, respectful and let your worries go away. Bring some bravado and next thing you know you're getting extra/s.
I always carry cash of 20s, 50s and 100s denominations. For 60 minutes massage with HJ extra, I'll handover $100 total after the session.