All Tenders can be set up by going to Setup > Function Descriptors. If you do not want the Tender to be used ensure that it is ticked. If Inhibiting the Cash Tender, note that the Fast Cash buttons can still be used to tender a sale. To hide the Fast Cash buttons on the tender screen, ensure that the Yes/No Option Show Preset Tenders is disabled.
Each Tender is able to be toggled to enable Cash Out or not. Tick to enable, un-tick to disable.