The one thing you might try is talking with a local lender like a regional bank or credit union and ask about portfolio products.Around here (Plymouth County) I'd talk with Rockland Trust, Eastern Bank, East Boston Savings Bank, Bridgewater Savings Bank and others like them.

Pen Fed Credit Union has the best HELOC's for rentals.

I would make a list of small local community banks and credit unions, starting with the ones you already have existing accounts with. 

I have 20000 down and the credit union has no problem giving my LLC the loan.

I’d suggest checking with a local credit union and the bank you currently have a mortgage with.  

Maybe a credit union locally might have a slightly higher rate of return? 

Auto Construction Loan from a local credit union How did you add value to the deal?

Using an Auto Construction Loand from a local credit union How did you add value to the deal?

@Manu Kaina IV reach out to a few local Credit Unions or small banks (as mentioned by @Andrew Beauchemin) as they know the area and would be happy to provide this kind of loans.

I've had good luck with BankNewport as well, to do rate comparison you can also try to get competitive quotes from other local banks that hold onto their loans, such as Pawtucket Credit Union, Navigant Credit Union and Coastway (now HarborOne).Other than the rate being a little higher because of it being 4 units and non owner occupied, is there a reason this would be hard to find @Hunter Waterman - have you had difficulty getting such a loan (HELOC)?