Ah Dear Danger Mouse,
I see the trap hasn’t caught you yet! Long may that be the case!
Some thoughts for you:
Buyer Advocates
Go in with your eyes open. The usual ways BAs role is that they lock up the deal, then try to shop it around. I would want to know if they have an immediate buyer. Beware the re-trade too at the end of DD (where they significantly drop their offer after eating up the DD time). Six months is a long time mate.
Subdivision
I’m inclined to explore this option with a town planner by setting aside a limited amount as a feasibility budget. That will also shed more light on whether the BA route is likely or not. You’re playing with profit here, so the more you know, the better informed you’ll be.
Building
Unless you are an experienced developer / builder, the $300k profit is not worth the extra risk, and aggravation, in my opinion. That said, I think the SW Brissie optics are strong until the Olympics.
Long live the mouse!