Go to www.coolhouseplans.com they have an average cost calculator for new homes
by region.

Also consider the tax impact of new vs. old construction.renovation. One trick
here is to try to retain the old home, or a part of it, when rebuilding so it's
all just a major "renovation."

And sometimes that is done by necessity. A home bulilt in the 70's will have
about a 5000.00 tax bill here, but the same home rebuilt brand new after a fire
would be more than twice that. Save one wall, and "repair" the rest and you
keep the old tax rate.