What I did was before I even started was move the Scott family to a new house before they were send to the middle of the ocean and their house disappearing. Or you can use Twallan's Master Controller and move them to your current house and then have them move to one of their own.
Edit for Crinrict. Not only does the Scott family's house disappears, but, the Happy Houseboat (it's empty when you start) also disappears. I hope EA can fix this.
Another edit: I started a thread on this issue is this forum. Hope a guru sees it.