I confused with why you would buy the acreage now and build over...

I confused with why you would buy the acreage now and build over 2 yrs if house prices are falling, and possibly crashing, for years on end.

I understand why. Because home ownership is priceless, even if that price is moving down. You have lifestyle goals to achieve and that's living in the now. And you clearly state the current home is important to your family with regards to your daughter's eduction, which in my opinion is a wise choice by you.