STR Calculator Troubles! Mortgages???

[David Tardy]

So I am creating a comprehensive spreadsheet that I can easily plug basic numbers into, (Will share once complete) including all STR specific expenses, but I have ran into some trouble when putting an equation together to churn out a reliable P&I number.

From my basic calculations so far I am getting almost half of what an actual mortgage calculator tells me. I take the Price - Down Payment * 1.05 (or whatever the interest rate is) to get my loan amount. Then divide the loan amount by the number of months to pay the loan, so 360. 

Why am I so far off from other calculators? 

[Jon Crosby]

Hey @David Tardy  Excel does this all for you already.  Here is the formula as well as a link to my spreadsheet if you need any other info that can help. 

~Cheers

Jon

https://www.dropbox.com/s/xwnw30cmjx32is1/Vacation...