Every bounty is different.
During ICOs, coin decks usually allocate a certain percentage of coins or a fixed sum that are used for various different bounties.
For media, usually the bigger the following, the bigger the bounty that can be negotiated. Your best bet would be to message the creator themselves to see what deal youncould work out.
Bear in mind that some ICOs are just get rich quick schemes so you're bounty reward may not actually be worth much if the coin doesn't take off.
I agree on this one since ICO do really have different allocations or percentage they put on bounties either on signature,media,social campaigns which means rates or potential income wont really be the same at all but earning potential would really be good depending if you do able to hit up the right project but if not then those hard work would really comes to waste and this is the risk on joining bounty campaigns since theres no assurance if the project would be success or would flop.