HELOC used for full down payment

[Steve Morris]

Hello I am a new member and loving this site. 

I am trying to buy my first small multi family income property. 

I unfortunately don't have the capital for the down payment saved up, but I do have good amount of equity in my home. I have 250k HELOC that I am planning on using to pay for down payment , closing cost and any repair costs needed.

After watching a few webinars about how to use the property calculator and learning about taking your annual cash flow divided by your total invested capital to get your ROI percentage.

My question is when you are using a HELOC, lets say 110k for the down payment how do I calculate my ROI? Do I divide my cash flow by 110k or do you look at it as a higher ROI percentage because I am not really using my own cash?