Focus on three things: State your intentions, show that you have the financial means to make the purchase and make a personal appeal to the seller. An Offer to Purchase Real Estate sets out the terms of a proposed real estate deal.Create yours now with our free form. Discover an impactful sample letter of an offer to buy property. Show sellers your genuine interest and secure a dream property. Here are house offer letter samples to win a bidding war. 3 examples to use as a reference point. Try not to go over three to four paragraphs. That's a big turn off to sellers. The buyer purchasing the property and assuming the existing mortgage.