Due diligence money is a fee that buyers proffer at the time they make an offer on a home. In essence, it is the buyer's good faith payment to the seller.Welcome to the due diligence period. Roll up your sleeves and break out your checkbook, it's time to get dirty and spend some more money. The buyer uses due diligence as a way to show their good faith that they are very serious about purchasing a home from the sellers. Due diligence fees are most frequently paid through a wire transfer or personal check. The due diligence fee is a fee paid to the Seller once the contract has been executed, essentially asking the Seller to take their home off the market for you. Understanding due diligence in North Carolina. Learn what it involves and how it protects buyers and sellers during the real estate purchase process. The due diligence money will become the seller's if you back out of the contract for any reason at any time.