Answer:
Total budget = $500,000
Down payment = $100,000
Loan amount = $400,000
Case 1
Annual rate = 4.5%
Number of payment = (30*12 month) 360
Loan amount = $400,000
Monthly payment = PMT(Rate, Nper, Value of loan)
Monthly payment = PMT(4.5%, 360, 400,000)
Monthly payment = $2,026.74
Case 2
Annual rate = 4%
Number of payment = (15*12 month)180
Loan amount = $400,000
Monthly payment = PMT(Rate, Nper, Value of loan)
Monthly payment = PMT(4%, 180, 400,000)
Monthly payment = $2,958.75