But as you've noted, you're not going in with any equity.

Positive cash flow....no possible way long term.Based on the opportunity value of your equity your properties do not have true positive cash flow.

Essentially almost ALL of the cash flow on the first paid for property had to go to pay off the notes that quick, but it allowed us to buy another 400K worth of good rentals for 'nothing down out of pocket' (just the equity we already had). 

If that value gives you enough equity then you don’t need more money down.I think most seller financed deals have an interest rate 1-2 percent above 30 year fixed.

My lender says you cannot take a home equity loan out on an investment property~ is that true of most lenders? 

Moreover seller would be in favor of seller financing because the interest they get from financing is higher than they would get anywhere else.

I now have just less than 10 years left on that mortgage and over 50k in equity in that property. 

Have plenty of equity so that is a loan option, but money needed for short term.

You spend more time.Start with QuickBooks, as you will know your numbers - equity and financials.

Essentially ignoring all the equity in my current residence?