Are you looking for Dr Paul Brewer's Unofficial HAMP Loan Modification Calculator

Version 2.5-beta has Tier 1 and Tier 2, principal reduction, lender's variation, and misc expenses and was released October 2012

If so, just click on that link. Please understand that, for many reasons, there is no warranty for the software or the calculations. Still, it is there to play with, study, learn something, and enjoy.

There's also a YouTube Video featuring the unofficial calculator

Y'all come back now