The Heloc can also pose as a debt obstacle since its an open end mortgage a.k.a credit card.a mortgage is also set up over 30 years so it offers a lower rate and payment. 

In addition your 17 so I am assuming your still at home.

We rehabbed the entire property and added an additional bedroom to each of the units.

@Alec Barnes we use Debt-To-Income Ratio (DTI) instead of income = 3x rent.Reason?

The technicals (migration rates, job growth, tax situation, debt cost, etc) to work as well.

@Ram Go "Initial Debt" may or may not be the same thing as the current loan balance. 

The major pieces of information you are missing include NOI which includes deducting all of your operating expenses from your gross rents sans debt service, market dynamics (what are vacancy rates and asking rents like in the market the building is located in?)

Do you have additional capital to add?

Both properties have a substantial amount of equity that’s essentially sitting idle.Would it be a good idea to tap into this equity (through a HELOC, cash-out refinance, etc.) to fund future fix-and-flip projects or purchase additional rental properties?

If you have the means to cover debt, you can avoid the accounts being liquidated.