Good morning Neil. The first 3 or 4 minutes of audio in the video was pretty bad. After that it was ok though. I don't know how hard it is to get clay in your area but I think that it would make better fill than sand. It would pack down harder and once it settles it won't move. That being said, looks like you're moving right along with your project. It just takes time and money when it's available. God bless and have a wonderful day. 👍👍🙂