I'm building a house. I contracted out the structural shell and exterior, then all the internal work I'm doing myself. Except for plumbing, I don't want to be responsible for creating a swimming pool. In my country there is no such thing as "permits", you can do any work on your own house without certifications. If I had gas I'd contract that out too.
It started when my ex and I were having trouble in our marriage (divorce will be finalised soon), probably after watching too many a YouTube DIY channels, and here I am a year and a half later :D
I moved in when it became livable 6 months ago (I had to shower at the gym for a month), and it should be finished sometime next year. I don't work that much on it though, as I am busy with my job and kids. Some rooms are nearly finished, others are barely started. I've got used to the concrete slab as a flooring and no doors.
Would I recommend it? Ummmm... probably not. But it's been an interesting experience, and I've learned a lot. I don't want to diminish professional contractors, as some of them are really skilled, but I feel you can get most of the way to "standard home finish" by watching a few YouTube videos on the topic. You will be slower of course and might need to repeat/fix your work, but then to push it to "luxury-ish finish" you mainly just need a good eye for detail.
An important lesson I learnt is the phrase "paint covers a multitude of sins" is wrong, as paint does not cover it, your mistakes will still be visible just in a different colour. Joint compound/plaster does though :D