A buyer mails full-price offer. What element is still missing to form a valid contract?

Consideration refers to something of value exchanged between parties to a contract. While it is essential for a contract's validity, the buyer's full-price offer already implies that consideration will be provided upon acceptance. Therefore, consideration is not the missing element, as it is inherently part of the offer and acceptance process.

Earnest money serves as a deposit to demonstrate the buyer's commitment to the transaction. While it can strengthen the offer, it is not a necessary component for the formation of a valid contract. A seller could accept an offer without any earnest money, making it an optional aspect rather than an essential element.

A contract must have a legal purpose to be enforceable. However, the legal purpose is not missing in this context, as the full-price offer typically pertains to a legitimate transaction. Therefore, while necessary for a valid contract, it does not apply as the missing element in this case.