How do you figure ROI on a rental property 100% financed?

[Mike Tremblay]

So a lot of people seem to tell me that I should know my ROI. But I'm unsure how to calculate that. I mean I understand that if I invest $1000 and make $100 over the course of the year then I got a 10% return. But I bought a rental property using my HELOC, I paid for everything using the HELOC. So the total cost of everything was $44k. All the money I get from the property goes straight back into the HELOC as I don't need the cash flow now, the idea is once it's paid off I'll have a little retirement cash flow. So it's been almost a year since renting it out and I've paid about $2k of the loan off. The taxes are paid for almost a year in advance. So I'm happy with the way the property is going but how do I figure out an ROI on it? Thanks.