My understanding is that even though there is a moratorium, the tenants are still liable for the debt.

BRRRR is the most efficient way to start/grow a small portfolio, but impatience expressed financially is debt, so you can't be shy about racking up mortgages.Once you get going with BRRRR you will get to a point fairly rapidly where your personal income streams that exist now could not cover your debt service payments for your investment properties and how far past that point you are willing to go will determine your growth potential.

They will also understand the higher debt to income ratio due to school loans.

This number is NOI (net operating income) after debt service.

You want to keep (roughly) the same amount of debt and just swap that out for new debt at better terms. 

You mentioned you have lots of credit card debt but also have properties that are owned free-and-clear. 

Even though refinancing is technically taking on debt, just like a HELOC, it feels different.

You haven't yet told us what cash flow this package produces, so there's no way of knowing how much debt service this deal could support. 

(That I have found)---My debt to income is currently in decent shape (until I finance another property?)

I know there are many other ways to fund a project such as a partnership or other forms of creative investing, but I will need to fund almost the entire purchase using debt.