I'm making the upstairs into a finished living space with kitchen and bath. Everyone who sees it asks how I learned to do it, and it's the same as anything else. It's all out there on the internet if you want to take the time to read and watch. I've done everything except pour the concrete for the slab, and install the roofing. I'm currently finishing out the bathroom, then I'll lay the hardwood flooring and it'll be done. It's been very satisfying.
The one thing the big box store had, that I wish I had gone to a lumber yard for, is PT 4x8' 3/4" plywood for the floor. I ended up using non-PT and painting it to seal it, but it still probably won't last as long. At least it's a couple feet off a bed of gravel, which should help.
Note, at a real lumber yard you need an account. They can accept cash sales but they would rather not. They won't talk to you if someone else with an account is there. Once you have an account (which is free) you have passed the initiation and they love to help.
Not to mention that the lumber at lumber yards tends to be of superior quality as well.
I did all the smaller stuff myself, including framing, putting together the roof trusses, and roofing (minus the sheathing itself). You can easily manhandle around dimensional lumber by yourself; it's long but skinny easily to easily handle, unlike sheets.
http://www.todaysplans.com/og2424g.pdf
I modified them to add a full size staircase in the corner, change the window and door layout, and add dormer windows upstairs. I got a permit and had the plans approved by the city. Once the slab was poured I just started framing the walls and went from there. I'm working mostly on weekends, so during the week I'll research the next few things coming up. YouTube is the best resource for fiddly things like how to solder a pipe, how to lay tile, etc. Websites with diagrams and pictures are more helpful with technical things like how to lay out window framing, how to properly vent drain pipes. I know I'm working much slower than a pro, but I don't mind, and I get to have things that would normally cost a ton extra for just the cost of materials.
Also a note since full-sized truck has been mentioned a few times, I have a compact truck (2005 GMC Canyon) and it has carried all of my supplies after I had the main lumber order delivered. A compact truck with full length bed is perfectly capable if you are working alone or with 1 helper. The amount of drywall I can hang in a weekend is about what I can carry in the truck. I have a bed extender that was less than $100 so I can carry 16' materials no problem, 20' if it's a short drive.
Now, when I visit newly renovated homes, I see so much corner cutting, work that does not meet codes and sometimes is unsafe.
Plus, the stuff does not change as quickly as software. If you learn framing, you should be able to construct a house for many years to come. Also, much of the building codes is just common sense and most of the time makes sense. Software is just so abstract compared to physically building a house.
The building inspector was impressed with my shed when he examined it. He said it was really sturdy, and superior in construction quality to off-the-shelf purchased sheds (which also cost a lot more than I paid for materials!).
My parents house kept getting water in the basement because of soil being sloped towards their house. Neighbor was too high and their house was too low. I ended up designing a solution, which was a retaining wall and french drain system. The last inspection, two inspectors came out and asked if I do that professionally because they have been impressed by the drawings submitted and the scope of the job seemed unreasonable to be tackled by a home owner. The older inspector said I should do it for a living and he thought there was no way we would complete the project.
Fortunately the land was overall flat, other than the problem with it sloping in towards the house, so that was sufficient to solve the problem. It sounds like you had worse issues with your terrain.
We removed a few tons of dirt by hand lol.....I regret not renting a bobcat.
> when I visit newly renovated homes, I see so much corner cutting
You could do construction with your knowledge. But starting a construction company means deeply understanding the economics of every little thing, which leads to corner cutting.
There are people who will pay you to build a good house, but most people just want it cheap and looks like the magazines.
If you simply do the research and follow it, which is will within the capabilities of almost everyone posting here, then you should be OK. The mistakes you'll make will be relatively minor.
And at 96 sqft, that's well within the range of the homes being discussed in the article. If I were doing it to live in rather than as a shed, I'd build a 12x16 or a 16x16, for 192 or 256 sqft. 16' is the maximum length of dimensional lumber you can typically find at a hardware store, so the advantage there is that the house has structural members extending the entire length of the house, which means it's super sturdy. 8' and 12' are also common lengths of dimensional lumber, hence the size of my shed. Also no surprise that the height is simply 8' (uncut lumber) minus the height of the floor.