Posted by Ernest Tew on May 21, 2000 at 07:04:55:

Without knowing how much a person will pay and when, there is no way of knowing the final payoff.

If you don’t have a calculator capable of figuring mortgage payments, you should get one and learn how to use it. You will find that it will be one of your most important tools when working with mobile homes, real estate and other investments. Prices start at about $25. You can work primarily with four keys: The number of months, the interest rate, the loan amount, and the monthly payment. To get an answer, you need to enter any three known numbers and then press the fourth button for the answer.

With the four numbers are filled in, you can then get a fifth number–future value. One example of future value is the payoff at a specified time.