This document provides information and guidance for music promoters on key costs involved in booking and promoting music events. It outlines several major expense categories including: [1] venue booking costs, which can vary from free space to negotiated deals; [2] paying performers, typically through guarantees or door splits; [3] advertising costs, which should be proportional to expected attendance; and [4] additional expenses like riders, equipment rental, accommodation, tickets, and sound engineers. It advises being clear on costs upfront and provides a mini budget exercise to estimate costs for a given event.