When financing a portion of a down payment using a Home Equity Line of Credit, should the credit portion of the down payment be included in your investment basis for the purposes of calculating COC and ROI?

A simple example:

You're purchasing a house for $500,000 with a 20% down payment.  Of the $100,000 down payment, $80,000 is coming from a HELOC, and $20,000 is coming from your pocket.

Annual income from rent is $60,000, expenses are $30,000, making your annual Net Operating Income $30,000.  You then pay another $20,000 in debt servicing for your mortgage and $5,000 in debt servicing to your HELOC, making your Operating Cash Flow $5,000 annually.

When calculating the Cash on Cash Return (OCF/Investment Basis) and Total ROI ((OCF + Equity)/Investment Basis), should we be using the total down payment amount of $100,000 or just the cash portion of $20,000 as the denominator?

Option A:

COC= $5,000/$100,000 = 5%

ROI= ($5,000 + $15,000 accrued equity)/$100,000 = 20%

Option B:

COC= $5,000/$20,000 = 25%

ROI= ($5,000 + $15,000 accrued equity)/$20,000= 100% 

Since the debt portion of $80,000 is being accounted for in-year through the OCF calculation, would we not be double counting it if we include it in the Investment Basis as well?