How to use equity to fund new development.

[Eric Mcginn]

I have a duplex in Maine that I have a ton of equity in. It also has a mobile on the property, all three units are long term rentals. 
I want to use that equity to get a loan to pay for a well, septic, and mobile home at a property I bought in Joshua Tree, San Bernardino County California. 
I've never done a HELOC before, is that what I should be looking at for this project?