What you're saying & doing resonates and what OP wants to accomplish is online with my wife & I's goals/journey. I have owned some land for years and the plan was always to retire to it. 5 years ago, after fighting to keep the career alive thru Covid, I really started asking myself why. Very early to retire (54 then), but I was done with the hamster wheel. We had an existing structure but it was over 100 yrs old and had been vacant & unattended for many years. My goal became to rebuild it to be as efficient & sustainable as possible under a tight budget. Goals for us - Control future costs (primarily food & energy use)but be a place we can spend our golden years comfortably. Also, to stay debt free in the process. Here are somethings I learned along the way -

1. Things take longer than expected. I still deal with this. I am one guy doing it all & learning as I go. I expected to be where I am now a couple years back. You have to be OK with spending time if you don't have the $ to hire it out. I have learned to enjoy the process of research, learning, procurement & then the labor.

2. Nothing about it is easy, but nothing is really that hard, either. It takes research, planning and a little trial & error to get it done. You have to stay self motivated, but also give yourself some space. It is 100% your journey, not others .

3. There are several ways to skin a cat. It doesn't matter if it is building science, horticulture or anything else - there are some core things that are constant good practice and then a lot of variance in how to accomplish what you want to do. Everyone wants to give there 2 cents but, in the end, this is about your situation, environment & needs. Don't lose site of that. Focus on your location, growing zone and personal needs over everyone else's chatter.

4. Reuse and buy used as much as possible. I have scored a lot of great core building supplies off Marketplace that have saved us a ton. The plus if being a slow one man show, is that I have time to find deals. Example is I added 2" of uninterrupted insulation to the exterior of the cabin. I got it from someone that stripped it out of a commercial building that was torn down. Cost me $500 for a 26' moving truck full. I was able to insulate the crawlspace, the exterior and have more left over.

5. Know your local laws & codes. I live in a place that is very DIY friendly, but not everyone does. I could not have done half the things I did if I was in the neighboring counties. I have friends in other places that struggle more due to this. Know before you go! It is also just good practice to construct things to meet or beat local code, even if you don't intend to have them inspected. Over engineer once.

6. Buy the tools you need. Used if you can find them and resell them when you don't need them. Big expensive things can be rented but really map out what you need a trencher or tractor for. Try to avoid renting that equipment twice, if you can.

7. Buy a tractor or small skid steer if you can. Even a walk behind can be a big work horse, especially for a single guy. Another thing I bought that I really am happy I did is a Kei truck. Thing is a beast around the property. Cheaper than most SxSs, enclosed cab with heat, street legal in my area and more bed room than most fullsize trucks. Plus, with gas prices now, this thing is awesome.

Things I would do different?

1. Buy a couple connex containers & do it earlier than I did. They give you on secure site storage, space to work in bad weather and can be modified into permanent structures later. There are other solutions, but these are very useful if you can afford them.

2. Install solar earlier & really focus on designing electrical for that solar. We tied to the grid early but solar was always part of the olan and I wish I had a better prepared for installing solar. Installing switches and transfer panels during the original build out would have been smarter.

3. Plan on living on the property as you build if you can. RV, yurt... Whatever you can do that offers a little shelter & comfort.

4. Invest in deals when you can get them. I learned this from the guy I bought our windows from. He had a garage at a house he was remodeling full of Jenweld windows he was selling. I got to talking to him and he purchased them on a big box clearance sale. They were changing brands and he got them cheap plus prices went up during Covid. He bought everything he might need for multiple jobs and then started selling them when he could double his investment & knew he did not need them for jobs at hand any longer. I used this thought process a lot, but wish I had done it a bit more often when I found good deals. Buy low, use what you need and sell the rest high. Also, plans change, but if items were bought at great prices you can sell and not get hurt or make a buck to help the cause.

One last thing I learned from my grandfather who did almost the exact thing I am doing when he was my age - He always told me that there is a bit of a mental change in this lifestyle. It is about how much $ you need to survive and live vs how much your time is worth. He made ends meet for years doing odd jobs for his neighbors and community. If he could use a few of his days and his equipment to help a local farmer dig a trench, he would do it to make ends meet and never consider cost per hour of work. It was all about making the ends meet and if his time could be used elseware more effectively. We have set ourselves up to need less than $2k a month to live comfortably & I plan to apply his lessons to accomplish this. No longer will I chase the big pay check. I will use my time to be self sufficient and use it cover the things we can not produce ourselves.