This can be a conventional loan, so I would suggest that you with conventional lenders for better rates and terms. 

It sounds like they are suggesting to you to establish series LLC = one tax return with multiple entities underneath one parent LLC.

Just a suggestion, I've had some luck using the approach; "obviously you don't like dealing with me, let's come up with a solution that works for both of us so that we can move on with our lives and not have to speak with one another ever again."

I am currently on the hunt for my first small multifamily property in South Jersey (Camden and Burlington counties) as well.While I have not used a property manager yet, a few local investors suggested Mike Williams of Sureway Property Management.  

Suggest you have it appraised.

The lender I am working with suggested a 5-year ARM with interest only payments.  

I am looking for working capital to expand my flipping business and was wondering if anyone had any suggestions or recommendations on this specific thing.

It would be helpful to know: rent growth, exit cap, business plan and your experience with such assets before offering any suggestions.

Does anyone have any suggestions on neighborhoods for good cash flow?

While you are doing that, do everything @Karen Rittenhouse suggested.