To enter how much you paid an influencer or their costs for a campaign, you must go to that campaign's page.
In the campaign's influencer section, you will see a label with "price" on the far-right-hand side of every influencer listed. You can input the pricing details here.
You can also add any additional campaign costs in the "overview" section of your campaign's report.
Next to "Costs" in the "Overview" section of your campaign's report, an ROI percentage will appear. This figure will be automatically calculated based on Lefty's formula: ROI = (EMV / Campaign's Costs) - 1
To watch a video tutorial on how this is done, view the demo below: