Pricing for charitable fund raisers is open to negotiation. Don't ask us to play for free. You pay the caterer. You pay for the facilities you use. Someone can pay us as well. The very definition of "professional" is that you get paid for your services. We are sympathetic to the fact that you are trying to raise money, not spend it. That being said, we can work something out so that we both benefit.
Payment terms are that we require a 50% non-refundable deposit upon acceptance of the contract to commit the group for your event. The balance is to be paid at the event, prior to the performance. Payment may be made by check or in cash. Payment for custom arrangements must be paid in full, when the contract is signed, and the commitment is first made.