What is the ruling on the salary and commission of a salesperson, and the ruling on the income of the company, if the company sells cars to customers in cash or through usurious banks from which the company receives the price of the car in cash, and the banks collect their installments from the customer?

It is permissible to work in the company if the work is lawful and not connected to usurious transactions. As for what is connected to usurious transactions, it is not permissible to work in it, nor to assist in it, nor to benefit from the commissions arising from it, unless the worker is poor and in need, in which case he may take from it what suffices his need. One should avoid prohibited transactions and stick to what is permissible, and it is better to look for work that is free from any doubt. It is not permissible for an employee to take a commission from a party other than his employer without their permission, and the commission from a usurious bank for referring a customer is forbidden. Your salary is lawful because it is in exchange for permissible work.