Bang Joni, who just got married, plans to buy a dream house at a price of IDR 2.5 billion. The funding type Joni's choice is with a 10-year Bank Housing Loan (KPR) and a down payment to be paid is 30%. He plans to set aside Rp. 15 million from his monthly income to pay mortgage installments for his dream house. Question:
a. How much installments must be paid by Bang Joni at the end of each month, if the interest rate is 10% per annum?
b. What is Bang Joni's plan with reserved funds? Can he buy the type of house that he wants? Explain your arguments if he can buy the house and provide suggestions if the budgeted funds are not sufficient