Using an online mortgage calculator (one is listed below but many exist) look at the monthly mortgage payments under three different circumstances. By different circumstances I mean change the interest rates, term length (15 years vs. 30) and the loan amount (meaning you would pay more or less of a down payment). I run a scenario where I borrow $200,000 for 15 years at 4%, a second scenario might be $200,000 for 30 years at 4%, and the last scenario might be $180,000 at 3.75% for 15 years. In a paragraph or two, write about how the three different scenarios differed and what surprised you about the process. It is important to remember that people were paying as much as 10% interest on mortgages not that long ago.