# Need help using my new financial calculator - Posted by Jim IL

Posted by Chris (FL) on October 04, 1999 at 24:00:05:

I have an HP 10-c & I’m happy w/it. Do you know of any important features the 12-c or 19-c have ( that the 10-c doesn’t ) that a real estate investor would use frequently?

Need help using my new financial calculator - Posted by Jim IL

Posted by Jim IL on October 02, 1999 at 21:09:38:

Hello all,
Well the other day the HP12C went on sale with a reabte, so I bought one.
Now, I’m playing with it and learning to use it, sort of.
I have to figure out what a payment will be on an interest only payment loan.
any ideas how to do this?
what numbers get put in where?

Jim IL

Re: Need help using my new financial calculator - Posted by Michael Morrongiello American Note

Posted by Michael Morrongiello American Note on October 02, 1999 at 22:09:13:

Jim
Without going into the specific keystrokes. Since this loan will not amortize but is interest only you typically will get an error message when attempting to solve for a payment amount.

Here is what I do;
Take the amount of the principal balance due on the loan and x Times that by the interest rate. This gives you an amount of annual interest due on that principal. Then take that figure and simply divide it by 12 months in a year to calculate what the monthly payment amount of interest would be.

Michael Morrongiello
Operations Manager

Re: Need help using my new financial calculator - Posted by Kevin Lee,TX

Posted by Kevin Lee,TX on October 03, 1999 at 23:14:03:

Michael is right.
But if you must use your calculator’s function keys for the sake of learning your calculator, this is how I do it. I have a HP19B, so I don’t know if the keys will be the same for yours.
For exemple, \$20,000 loan for 5years. 10% interest only…
Put 20,000 for your PV. put 60 for number of payment put 10% for interest and put -20,000 for your FV(future value) and press PMT(payment) key.
Have fun.
Kevin