I have a 10000 sq ft house half way built about to be under contract. Was wondering how do I figure out arv if there are no houses that big anywhere near area?
It certainly sounds like you have one that's different: half way built, no houses to comp and it's 10,000 square feet. I'd recommend not spending much time on this one. But if you want to see it to the end maybe ask a Realtor friend or an investor at your local REIA to give you an idea of value.
Good luck with it.