If the company is a single tax payer and wants to sell the 3rd car...?

The income received by the taxpayer from the sale (exchange) during the reporting (tax) year of the third and subsequent objects of movable property in the form of a passenger car and/or motorcycle, and/or moped or other vehicle is subject to taxation at the rate of 18 percent from the value of the object of movable property.

There is no difference.