@Clary-Roberts - glad you got the duplicate listings resolved!
I just posted some detailed info for you under another thread for the calendar update, but you mentioned updating to iCal on that thread. Here, it sounds like you want to sync with your HA/VRBO listings. I can help you with that.
First, just to clarify, the listing with HomeAway will also include VRBO and VacationRentals.com. It may even include a few others like Cyberrentals.com. The content will be the same, but they just format those listings a little differently.
Now, if you're trying to manually sync with HomeAway listings, it sounds like you do NOT have an integrated listing, so to sync, you'll follow the same overall steps that I outlined in the other post, but choose HomeAway instead of iCal as your sync type.
Then instead of opening iCal, you'll go to your HomeAway listing, go to the calendar page for that property, and click on the little calendar icon in the corner between the + and the printer:
You'll choose import, and then copy the URL there to set up the sync.
I'm sorry I can't add more photos of the process, but my listings are integrated, so I can't mirror through that for you.
Hope that helps!