We stayed at Rebecca's place for a week over our wedding and couldn't recommend it more highly. The place itself is stylish, but still very homely and we really enjoyed spending down-time there. The highlight of the property for me was the outdoor entertaining area, which had everything we could have wanted (including BBQ/fire pit/swings and lawn games).
Barwon Heads is one of my favourite places to visit in Victoria, and The Shack itself is pretty conveniently located, an easy drive (or short walk) to the main street of town/ nearby beaches.
Rebecca is a fabulous host - very easy to get in contact with, responsive and flexible. She very kindly allowed us to have a few of our friends and family come over throughout the week, which made our time all the more special (and when we left some belongings at the house she went out of her way to assist us!!!)