A HELOC carries a higher rate over a shorter amortization usually 10 or 15 years and a mortgage carries a lower rate over a 30 year amortization offering a lower payment.You have to run the math in each scenario because the math differs based on a few things like Fico score, CLTV, Loan size, and time frame between purchase and refinance of new property.

I have the credit score and make a good monthly living but I have no cash save up but have 2 cash flowing rental properties with one of them having some equity.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

FHA loans with low down payments are ideal for this.In the meantime, focus on improving your credit score and maintaining a solid financial foundation.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

In Colorado specifically, we’re also losing a lot of options due to an increase in our wildfire risk scores in many zones.  

@Melanie BaldridgeWhat is the tax implication if I swap one property for another that is valued at lesser amount. 

A U.S. credit score wouldn't be required but more money as a down payment would be.

Not a big score but forces you to learn.  

My fiancé and I have been saving and working on our scores in order to buy our first home.