Down Payment Choice - Refi or HELOC?

[Christopher Freark]

When I moved two years ago, I turned my old SFH into a rental and currently have a $400/month positive cash flow from that property. I recently did a ELOC on that property for the down payment on a third property and I'm making about $250/month on that one.

I currently owe about $170K on my primary residence that is worth around $250-260K. I'd like to purchase another property (yes, I have the bug!). Which makes more sense to get another down payment, refi my current 30-year 4% loan and take a cash-out, or get a HELOC?

Thanks in advance.