I think it highly depends on how well you choose the bounties you participate in. They usually pay percentage of their ICO, so the more successful project you choose, the more you earn. The rewards can thus vary widely, probably somewhere between $100 - $10k per let's say 3-months running bounty campaign.
What are you looking for when trying to establish the best bounties? I'm new to this and want to get stuck, there is just so much to learn.
I'm not the one you asked, but usually you should check the team developing the campaign (use google or linkedin) it's also good that you keep an eye on the whitepaper, nothing very detailed because it can be exhausting, but if it's not a copy of other famous whitepapers, it's also important that you see how many tokens the bounty will take as it that gonna decide your payment.