Hi Miranda,
It sounds to me like you want to be a part-time developer, which is a very lofty, fraught with financial disaster opportunities, goal.
As Bill points out, there are few builders capable of great fit and finish of this type of building, that means you have to be so confident in their abilities that you won't be worried about the home guarantee.
Since you are going to end up being the seller, you are the one that will become liable for any failures of the home, not the builder (except to you, this means
should there be a guarantee claim you are the one that has to go after the builder to fix it, not the purchaser).
If you are planning to build this roundwood/ strawbale house yourself, you first need to know the ins and outs of building such a structure. If you don't have the skills then you will need to first acquire them or hire someone with them.
The other part of this idea is the time it takes to actually build such a structure. If you went to the location every weekend, how many hours would you actually be putting into the construction?
I live on my land and work the week days 35 miles from my place, I rarely get more than 10 hours in on actual construction in on a weekend. True I have to take care of animals but that is only about 1 hour per day.
My Saturday starts with getting up at 5am, I get dressed, go
feed the hogs, change their
water, check their bedding then it is back to the house for breakfast (my wife prepares it while I do the hog chores).
I usually head to start construction around 7 am (when it gets light
enough for the work).
I pull out the tools needed, then get everything setup and now it is already 8 am. I stop at around noon for some lunch and get back to work, then about half an hour before darkness I have to put everything up and wash up for supper.
Sunday is a short day since I also have to
shower so I'm clean for work on Monday morning. During the work week I am away 12 hours (work is 8 of that the rest travel time from home to back home). Now that it is winter, we leave in the dark and get home in the dark.
It's a grueling schedule, and I don't have business debt or student loan debt to pay off.
I own my land outright as well as everything but one of our two vehicles.
Since you state you already have debt for a small business and student loan debt, and now want to add to that stack purchase of land and building a house, all while not being present at the location full time.
This is a challenge not many would even think of attempting.
So much can go wrong, Perhaps it would be best to work at paying off your current debt load and then saving up for that eventual move.
I like to see people attempt challenges but I also like them to know the cold hard facts of what it takes to succeed at what they want to attempt.
I do not like to see people fail and become discouraged or go broke.
I've seen many start with high ambition only to fall into despair from lack of knowledge on the front end.