Keep in mind that sending the transaction does not automatically mean you will get rewarded for it: other Keepers may also be monitoring the job for work, and if their transaction gets mined before yours, you will not get the reward!
If we take the following transaction:
This failed: Fail with error ‘UniswapV2Oracle: !work’
The transaction which got the work was in the same block and the same gas price:
There are a number of discussions in the Keep3r network forum about profitability that you may want to follow.