Who would most likely create a double contract?

A double contract typically occurs in real estate transactions when a buyer and seller create two separate agreements regarding the sale of a property. This situation often arises when the parties want to convey different terms to different entities, like a lender and another buyer, to secure favorable conditions or financing.

In the context of the options provided, the relationship between a buyer and seller is most likely to lead to the creation of a double contract. The buyer might want to negotiate terms that could differ between what they present to the seller and what is communicated to a lender or a third party involved in financing the purchase. For example, the buyer may agree with the seller on one price, while simultaneously engaging in a second agreement that details a different value for the purposes of securing a loan or dealing with another buyer.

While brokers and sales agents or brokers and sellers play critical roles in facilitating these transactions, they are typically involved in the representation and negotiation but do not create the contracts themselves. Thus, the buyer and seller's direct involvement is what leads to the creation of a double contract, making this option the most suitable answer.