also noting most people arent' aware but the credit score run by a mortgage lender and say a general lender like a bank are actually going to be different scores (and likely slightly different ranges) - with some greater weights on mortgage debt for the mortgage lender Credit Bureau settings

Tell buyer, 1) I don’t have funds required to close. 2) you can raise your offer to the amount needed to pay off both debts or walk away. 3) it’s going to auction in 2 months.

So I did that and my property revenue cannot service the debt but using my strategy I'm cash flowing $1100/month after PITI on a new construction home under warranty. 

Leverage in an IRA will produce Unrelated Debt Financed Income (UDFI), subject to Unrelated Business Income Tax (UBIT).There are plenty of investment options to deploy your IRA funds, but again, using your IRA in connection with this transaction will disqualify your IRA. 

If you use debt to buy the real estate the IRA will incur UBIT so educate yourself on that. 

5x is a bit much to assume.Did your PMC pull credit on cosigner to figure out their debt load?

The only way you can break that log jam right now is severely lowered fed rates, but the level of federal debt is such that they're in a no-win situation because there's going to be little appetite these days for buying 1% fed notes from overseas.The fed rates were kept too low for too long.

The tax debt was about $7k on the property. 

@Muhammad KashifMost debt funds are equity only as they don’t take on leverage and are “cash only” when they acquire / lend on assets

You should refinance your long term debt into a DSCR loan and then do a heloc on your property.