Is it permissible to buy a car from a company that increases the price if the amount is not paid within five years?

What we understand from the question is that the company's condition of increasing the amount of money upon delayed payment is considered explicit usury (riba) and is forbidden by Islamic law. It is not permissible to purchase the car in this manner. The late payment penalty is usury and is impermissible. Dealing with usury is forbidden because it is one of the gravest sins.