Really, just because he's on an app like Grindr and happens to have brown skin, doesn't mean it's ok to ask him how much for a short-time, or how much to make a video, etc.
Seriously, would it kill you to spend 5 minutes of your life to figure out if he's a money boy or not?
Some of these guys are doctors who just bought a house... and some are so poor they're having bamboo and snails for dinner, but aren't willing to take their pants off for any amount of money. And every thing in between.