When I was growing up, I didn't have a tree house. I'm sure there were many kids that didn't. My family wasn't much for physical activities & adventure. Our pursuits were always more cerebral. They also weren't really the DIY types. At least, with certain projects. Back then, I believe, tree houses were more for boys. Today, girls/women are fine admitting that they enjoy things that used to be considered more the domain of boys/men. That probably includes tree houses.
There is a show on Animal Planet called, Treehouse Masters. We've never actually seen it. Since we get our shows/films through streaming. They create tree houses that adults could live in. I used to climb trees as a kid. Of course, these were just short ones. We had Gravenstein apples on our property. Now, I'd need some assistance. It would need to be a good stairway. As I am somewhat disabled & walk with a cane. Prices for building a tree house, to live in permanently, range from $9000 to $500,000 depending on what you want. Below is a three story one in British Columbia.
