It's often difficult to determine whether a particular car's intended use was for consumer or business purposes. Many people buy pickup trucks that are useful in their work, but are used primarily for personal reasons. Then are salespeople who use their passenger cars for both business and personal use.
Courts basically use one of two tests to determine whether consumer use is present.
Courts in a slight majority of states use the objective test to interpret their lemon laws. The particular intent or the particular use of the buyer is irrelevant. If a vehicle itself passes the objective test, it doesn't matter whether the buyer is a corporation or an individual. A slight minority of state courts uses the subjective test to determine lemon law coverage. The test doesn't look to the vehicle's normal use by all purchasers, but instead at the intended use of the particular buyer.