Hi, we only stayed 1 night at Suzi's place, and we loved Waiheke island! Suzi is also very quick in answering, and the appt was really clean and nice but small. Officially it's called a villa, because it's free standing, but it feels like an appt. And then she even upgraded us to the appt with 2 bedrooms! That was really nice btw. Also the car we could rent for 35 dollars per day was perfect. I had to pay a bond of 1000 NZdollars via Paypal but after a few days it was back in my account.
I would certainly recommend the place, not in the last place because of the convenience of having a car at a cheap price (check first if the car is available!)