Just a comment on the ac. Yes ducted heating is standard. Pretty sure heating has to be provided. It's not a luxury inclusion. But it will be ducted to the relevant ducts sizes and fuel. When you do an add on cooling system, the heater has to be upgraded to allow for a bigger fan and as such the ducts have to be bigger too to support the airflow. You'll find that add on cooling systems aren't going to be an efficient way or nay even a possible way to cool such a large house. Ergo, the ducted heating is moot. Why pay to upgrade these things if when you hand over you get told the addon cooling won't be enough and you'll need a reverse cycle electric unit? See where I'm going with this?
You're seeing these inclusions the way they are designed to be seen. You think you'll do this thing, or get this thing, then when you're 5% deposit in sitting in your electrical appointement, you'll learn you've seriously misunderstood what youre getting vs what you wanted. Then it's a matter of coming up with all this extra cash or pulling out and losing the deposit. What do you think is the common outcome at that point? Most people bend over and take it. They're emotionally and financially invested.
I suggest taking a trip to the selection studios and getting a tour and prices/upgrades explained, touch and feel the finishes and get a better ball park idea of what you're in for. At least you can prepare and lube up before the main event.
This made my day "At least you can prepare and lube up before the main event." so funny!