More important than any other factor in your search for the best event staffing in LA, is experience. You can't teach staff experience, it is only earned through time. Having a team that already has worked successfully in wait staffing means that you are assuming less risk.
They already know and can do the job, they've been trained, they are already certified, and they know how to think critically and quickly on their feet to problem solve for different situations.
So be sure you are verifying your waitstaff's experience to guarantee that the experience they claim to have is in fact true.