I really doubt the modified loan is fully amortized.
There was an article in UT Sunday Business section about a family did a loan modification, lowered their monthly payment from over $2k to over $300. It is cheaper than rent but the catch is that it is not fully amortized and there is a balloon payment at the end. I am just too lazy to look for the article in UT, but I am pretty it was within the last two to three Sundays.