Working to convince a potential buyer that a single$-$family house near a university could be converted to student housing, a broker guarantees the buyer that a future suit in a substantial profit. Such a guarantee

Maybe unethical but is not violation of the real estate rules and regulations

Requires comparable sales information to support the claim of future value

Is an acceptable professional practice if the property is properly zoned

Constitutes failure to engage in competent practice under the real estate rules and regulations