For example, if a borrower owes $100K (UPB + back payments), and the asset is worth $125K, I don't waste my time on these deals as the borrowers will fight you for that equity, and the sellers will often want a near payoff bid based on that you will be made whole at the auction.  

It looks like you have a solid basis for what the ARV for the property will be.What about the borrower himself?

Borrow - pay back, rinse, repeat.

If this is something you would be willing to do, then I would be happy to share the profits this first time and then become a HM borrower moving forward at a rate that works for both of us."  

(Same sort of thing happens between 15 year and 30 year) The additional time does not substantially impact the borrower's payment.

I think folks need to be realistic about their ability to borrow and or the unicorn rate that you think you can get.. loans are pretty universal .

In other words find someone who can be the primary borrower. 

Notes have "set off" provisions that allow a lender to add any other amounts owed by a borrower to that existing loan.

You do not need to have to jump through any the hoops to borrowing any money.

I borrowed some from my 401k and then got an additional $30k with the 203k loan.