Yo it really does depend on a lot of factors.
From my personal experience:
Buying gold: Extremely low ban rate, bought over 500b, never got banned
Selling gold: Fairly low ban rate, sold over 500b, never got banned, but there are plenty of sellers that get hit from time to time. Trading in members, with a high level account, not trading 100 people a day, minimalizes this risk a lot.
Buying accounts: Extremely low ban rate, never had an account banned after it was sold ( sold over 250 accs ),
Selling accounts: Same as above.
User services: Highly depends on the geo-location of the worker. I've had 0% ban rates with EU workers, but Venezuelean workers do get bans from time to time.
Botting: Not a RWT ban, but high ban rates
Bot farming: Somewhat high ban rates. It does depend on how well you would mule everything and on how big your bot farm is. I have friends who tried to bot farm. They started with only 5-10 accounts, and one day got banned on their main account as well ( they used this account just to give bonds, different PC, different IP ).
I hope this helps!