What should my next step be?

[Paul Baghis]

My wife and I own and live in a 3-unit house, purchased in 2015 for $400k with conventional financing and 20% down. Last year, we took out a HELOC on this property and used that (plus some cash of our own) to purchase a 6-unit for $875k with commercial financing and 25% down. We now own 9-units including the one we live in, and both properties cash flow.

We'd like to keep going and acquire more units. What would your strategy be if you were in our position? Not interested in anything too risky as I feel we've set ourselves up well for the longterm. Our personal cash is basically tapped from the last purchase. Do we now play the waiting game and let the combination of equity growth and likely appreciation do their thing until we're in a position to borrow again? Or are there other options on the table in the nearer term?

Thanks in advance for the suggestions. We're in the Portland, ME market FYI.