This proves once again that posting here is alway a wise first step. I am getting much advice, information and support and it is very much appreciated. I mean that.
I will think over my strategies - with the input received here.
Possibilities and likely: (all will be documented in emails)
Let them know that they will be in breach, but that settlement is a far better course - and make an offer to pay some of the increase - acknowledging they are getting hit with increases - but not my fault - and agreeing on any other details that may present issues going forward.
Depending on how that goes:
-cancel and get the refund (BTW - the builder said he hopes I will not cancel)
-get bids on the existing and approved plans
-consider tackling the build ourselves - and perhaps downsizing what we contemplated
-consider a totally different plan, a log cabin kit, or other options.
(I do see cabin kits at reasonable prices - downsized from what we were going to build, but recognize the issues they present)
-talk to some of the locals as to what they might be able to help with.
I will discuss all this with my (uber deserving) daughter and SIL tomorrow when they are both here.
BTW - in reliance on the agreed to contract price we proceeded with, and budgeted for everything else - well drilled, pad, road septic test holes, pump installed, water tanks bought and delivered and pad built for those, water yield tests and more.