I haven't even begun to be rude, quite frankly, I have been quite civil in my attempt to find out what forms I need to file for these 2 clients.

The father (seller) will file on Form 6252 & 8594 as I was told in the beginning of this chat torture.

Since then there has been nothing but "teachable" moments with no resolution. Don't get me wrong, I love that I am being taught things, learning is good. This however, for me will be a one time thing that I will never get involved in again, and I just need some helpful advice...

I can show the Amortization on Form 4562 Part III Line 19e Using "MM" and "S/L"  in column e & f, (not sure if those are correct or not, but they fill in the space without errors), which flows the "Depreciation deduction" (that I have been looking for the whole time), onto the Scd C. Perfect!

Now on to the other yet unanswered question... How do I show the Interest Expense on the son's return? The father gets the Interest Income via the 1099-INT that the son gave him, that's easy. How does the son write off this expense?