v. Buyer will provide written verification of down payment funds in the amount of no less than $XXX,XXX upon signing of LOI. vi. Buyer and seller agree that seller is responsible for the payment of brokerage fees to XYZ Brokerage, Inc. in the amount of $XXX,XXX.
That is about it for the content, believe it or not; it is direct and straightforward without any fluff or nonsense. You are simply covering each detail so the seller knows exactly what the buyer intends to do. Having an informal letter of intent also allows for easy negotiations.