@Joe Shay
In this scenario, I would do a comparison of the pros and cons of each:
HELOC
Tapping into equity that is not really being used.
Keep your immediate cash to be leveraged for other acquisitions.
Relatively easy transaction (from a documentation standpoint)
Paying interest on the funds used (this should be factored in your acquisition budget).
Lower overall return
Using your own money
Potentially higher cash flow
Less paperwork - no need to secure two loans (HELOC and traditional)
Reduced capital
How does this individual transaction play into your long-term goals? How fast are you looking to secure other properties? The biggest thing is that you have a property (not really an asset since is not generating any income) that is not really being optimized. If you are close to retirement and want to make sure you have no debt then that could be a different play, otherwise, I would look into putting that property to work.