Then refi with my bank for 30 years.

But each LLC should have it's own bank account. 

Hey Aaron, have you considered a commercial mortgage from a local bank like First National or Bangor Savings Bank? 

For example if the house is worth 400K, but they are willing to sell it for 375k because they are avoiding having to pay 25k in agent fees, then the bank can consider the equity gap as a down payment.

The idea is to expect a negative cash flow, however bank on the growth to achieve a good return.

What matters more is whether the borrower in question has the (i) time, (ii) contacts, (iii) experience, and (iv) ability to effectively communicate & package their loan request to banks & credit unions in a way that is compelling to those lenders. 

Neighborhood Scout is not going to cover any shortfall you have if it doesn't materialize.you could try finding a bank or broker that will do 80% out on a refi, although probably not possible to close by the end of this month. 

You started by saying that you have Local bank relationship. 

Some credit unions or local banks offer portfolio loans that don’t stick to the 4-unit limit, which could work well here.

I like the other recommendations, give them a seller financing offer that is their asking and a good interest rate with terms that make sense for you, and offer what the bank will let you offer.