"....which is quite expensive where we are ($125,000 for a 7 acre lot)."

That is dirt cheap relative to this area (min $70K/acre). So relatively, rejoice.

People in prior generations did this (living in the basement or garage while building)often. Current zoning laws might not permit it anymore. Need to verify.

You need a strong marriage. Things take longer, costs can go up and wants/needs change going through time. Have a mutual assessment of your goals and tolerance levels, now and periodically going forward.

Know the heating/cooling climate and building strategies thereof for your area very well when designing. The best money spent is that for energy cost containment. Very difficult to do after the fact. If you are framing, look into new framing techniques; ( Joe Lstiburek calls it Advanced Framing, but there are other names for it) basically less material use in conjunction with energy efficiency without any loss of strength.

Buying an existing property is so much cheaper with today's down market. You need to investigate that possibility fully before even thinking about buying property. See what 200K cash plus a bank loan can buy you where you live before you start property shopping.

85K will not be nearly enough to get you to a dried in stage in order to be able to actually live in a portion of the home. You'd need to do have utilities run, dirtwork, foundation work, rough electric and plumbing, framing, roofing, siding, windows and doors before a structure would be weather tight enough to be partially habitable. Beginning a large and complex build without enough capital and no plan for a loan is a huge disaster in the making. For a cash only build, the majority of cash should be earmarked for the build/not the land.

You need to rethink this and approach it perhaps from a more conventional perspective with a construction loan and/or builder involvement. Or perhaps you buy less expensive property and greatly scale down your home plans. Or you wait after you buy the land until you have enough cash reserves to complete the project to a dried in stage. Or you buy that existing property with 100K down and use the other 100K for improvements to it.

Wbowen.... Oh how I wish you were further along!! Were building the mcginnis ferry with a few minor changes/ we added 3 car garage and brought the house out 3 more feet to make the garage deeper. I haven't found anyone that has built this house. We are still having trouble coming up with the exterior look that we want! Do you have any idea what your going with? Were subcontracting our house ourselves and are just now in the process of getting all our bids in! Wish you the best!

WE wanted to build the basement and frame up and live in the basement while we completed the build.

This was common when I grew up in rural Ohio more than a half century ago. Things may have changed since then.

Did you run into any structural issues with this design? What type of exterior finish was selected?

My husband and I are currently OB our home on our houseless and barnless farm. We live in PA. Not sure where you are but there is NO WAY we could have gotten past the zoning officer, building inspectors, or even obtained a permit to do what you are concidering.
We even thought about doing a barn first with 'amenities'
and this was nixed by the local yokels.
Friends of ours did this in Texas several -5- years ago and pulled a camper into their barn for the 2 year duration of their build. But they had well septic and electric from the old tear down to work with.
As for the $--
We have acreage and getting the driveway, electric access, water plumb to basement, excavation, well and septic, plus all of the permits and plot plan by engineers was around 60K that does not include Basement pour or framing.
In my township permits are only good for one year then you have to have good reason for not bringing it to completion.
Not saying it cant be done but you have to discuss with your locals for the feasibility and try to be realistic about how much you want to do yourselves.
And there is the point that RE costs are down and if you dont already have the land and enough cash to complete the build you may want to really study the numbers for your situation. Finding an acreage with an existing house to extensively remodel cuts all those upfront "utilities" issues plus you have more leaway with the permiting process. At least in my neck of the woods. We've done it both ways and its much easier to remodel Extensivley than deal with the new regs for new construction.
Good luck and dont be fearful - you can do anything you put your mind to and long as the CEO lets you.