You can give staff, waiters and cashiers their own password levels (Settings / Employees). And give them a job restriction, like a cashiers and managers are the only ones that can cash out a sale.
In the Settings / Security you can control many of the functions that a password level can perform. Such as opening the Cash drawer.
"Does a good job" - That's a little vague. You should check the z-out reports. Look at the Activity log for things like changing a tickets after the sale or opening the cash drawer. Also, use the reports for Voids, Returns, Discounts to see how often that happens.