If you have bank loan (not an agency loan) or no mortgage at all, an LLC is certainly an option.

This allows you to access funds while keeping your existing mortgages intact.Second Mortgage: Explore lenders who offer second-position loans on investment properties, though rates will be higher.Cash-Out HELOC : While traditional banks often restrict HELOCs on non-owner-occupied properties, some portfolio or private lenders may offer HELOCs for investors.With $15-20K in liquid funds, look for deals where you can negotiate terms:Seller Financing: Negotiate lower down payments or interest-only periods.Subject-To Financing: Assume the seller’s existing mortgage while covering the down payment.Lease-to-Own: Lock in the purchase price while using rental income to build equity.

If they're working with a bank/CU, then it's even less.

As a business owner myself, I just couldn't imagine failing a client so miserably and then trying to charge them extra and being ok with that, and THEN, telling them that sharing financial data is standard procedure.

@Penny WilkinsonIf there are no comps, then I would try to ask community banks what they would be able to lend on it.

I would, If in this position, take the equity in the form of a HELOC and purchase a cash flowing asset that would not only pay for itself but pay for the cost of the money while putting cash into my bank account each month. 

Sounds like the velocity banking stuff that was popular for a while.

My attorney told me in 30 yrs he has never seen bank enact due on sale clause but he has seen multiple landlords get sued without LLC protection.  

Quote from @Gregory Banks: I would hire a structural engineer. $1,000 inspection could save you tens of thousands.

Not easy to do with bank financing.