To help you figure it all out with minimal hassle, this 3minute guide to offer letters shares insightful answers and info for homebuyers. Your letter should explain why you're interested in buying the house and include details regarding your mortgage financing and expected closing date.Here are house offer letter samples to win a bidding war. 3 examples to use as a reference point. Let's walk you through how to review and present a real estate purchase contract as a listing agent.