Can I get more properties?

[Erica Nagle]

We are currently waiting for our first fix and flip deal to close so we can start work. It's a short sale that was supposed to be approved by the bank but of course there's always more crap and waiting on the bank. Honestly why is it so difficult for the banks to get a simple approval and letter out? Don't answer that, I've worked for large companies and know why getting anything done is next to impossible. 

Anyway, the purpose of this post is to ask how we can go about growing our rental portfolio. We currently have 3 rentals, all cash flowing and I want to use the equity in these to buy more property. I keep hearing about reusing equity/cash you currently have in existing properties to buy more. How do I do this? We have a good amount of equity but how do you get at it? Is this a refinance? A home equity line of credit? I figured we can't get a loan to buy anymore because we don't have a regular income. 

Do we have to wait until our first flip is done (and maybe more) so that we have cash or can we leverage existing equity? Thanks in advance!