CoC is a metric I see used when a project is being financed, so that the cash an investor has in is, say, 20% (the down payment) of the value of the asset. This is what gives you a relatively high (hopefully) CoC return. The difference with a rehab is that it probably isn't financed, so you have 100% being invested instead of 20%. Hopefully your 45k increased the value more than 45k, but almost certainly you didn't 5x it like you would have gotten if you had used the 45k as a down payment on another property. To make the CoC look much better, the thing to do now is cash out refinance. If your 45k increased the value of the property 70k, and during the time you've owned the property the property value went up, you might refinance 50 or 60k out. In that scenario, the rehab would cost you Zero cash and the rent went up, giving you an infinite CoC return (on the rehab work. Probably not infinite on the property as a whole.)