Jack borrowed money last year to buy a new car. The loan is a 4-year loan with 48 monthly payments. The annual interest rate is 12% compounded monthly. The monthly payment for Jack is $300/month. If Jack is considering paying off this high interest rate loan by borrowing money from his parents, how much money does Jack owe and need to borrow right after he paid the 18th payment at the end of 18th month?