His original debtor passed away and a family member is the personal representative.The auction is being handled by an established local auction house.The creditor has told us the personal rep can not cure the default which is about 45% of the market value as is.

You might make a little money by notifying the Debtor that you intend to challenge the appraisal or the percentage of your payoff and get a tiny bit more from them so they avoid the cost and delay of litigating it.

These notes are assignable by the seller/lender, so a note investor is one who would purchase the note (usually at a discount) from the seller/lender in order to receive payments from the buyer/borrower/debtor.

All that to say this: I think there is an acceptable amount of debt for a business to have, but I want nothing to do with personal debt, or putting my personal assets at risk (no matter how small.

I have a great steady job making $70k and I'm bouncing back and forth between using my savings to pay off my debt or purchasing a multi-family home and house hacking. 

With with a Chapter 13 bankruptcy you or your servicer will be working with the debtors trustee to determine a repayment plan on both pre-petition and post-petition amount due to you as the lender.

Should I hold and start paying off debt or go for more?

That is a rule that says the property is owned entirely by both parties and unless both parties are liable for the debt, then no debtor can attach any part of it. 

I reached out to my network and got quite a few that are good for Debtors, but I am looking for one that specializes in helping Creditors.

What does the debtor intend to do?