Use Report Data in PDF Butler.
Be aware that Salesforce has to run the Report for us to be able to use the results. Running Reports in Salesforce is slow. So, if you can use a DataSource instead of a Report that would be better for performance.
Report field Label vs Value.
The report will already format the amount, lookups (eg lookup to User or Account), … . See the video on how you can have the raw value instead of the formatted value. The raw value can be used to use the PDF Butler formatting or to do calculation (see SINGLE_FOR_FORMULA)