If a seller accepted a contract on a house knowing the buyer is under 18, the sale is considered?

When a seller accepts a contract for the sale of a house knowing that the buyer is under 18, the sale is considered voidable. This is because a minor, generally someone under the age of 18, does not have the legal capacity to enter into contracts. In many jurisdictions, including Arizona, contracts entered into by minors can be voided at the option of the minor. This legal principle exists to protect minors from being bound by agreements that they may not fully understand or may not be in their best interest.

Once the minor reaches the age of majority, they may choose to affirm the contract and enforce it, or they can void it if they wish to do so. This flexibility allows for the minor to escape liability under the contract if they believe it is not in their interest. In this case, while the sale is valid upon acceptance, it remains voidable at the discretion of the minor.

The other options are not applicable because the contract is not automatically void (which would mean it never had validity), illegal (which implies a criminal aspect that does not exist in this context), or enforceable in the traditional sense since enforcement hinges on the minor's choice after reaching adulthood.