What type of contract is referred to as a unilateral contract in real estate?

In real estate, a unilateral contract is one in which only one party makes a promise or commitment that can be enforced, while the other party does not have an equivalent obligation to act. The option to purchase exemplifies this type of contract because, in this case, one party (the seller) grants the other party (the buyer) the exclusive right to purchase property at a specified price within a designated timeframe. The seller is bound to sell if the buyer chooses to exercise the option, but the buyer is not obligated to do so, making it a classic example of a unilateral contract.

Unlike the option to purchase, a bilateral contract involves mutual obligations, where both parties promise to fulfill certain conditions. A lease agreement also represents a bilateral contract, as both the landlord and tenant have obligations to each other. Similarly, a listing agreement represents a contract where both the agent and the property owner have responsibilities to one another for the sale or lease of real estate. In contrast, the essence of the unilateral contract is that the obligation falls solely on one party, which is precisely what defines the option to purchase.